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1. 13 L2 JAcknoswledenienlo uade uie RH nO Qin epi Ha 14 1 3 Problem Seabee ial oec eter 15 14 Operating eoe cii ehm ee IRE ENR NR LEE MUR ERN CUR NH 15 1 5 Intended Use and Intended Users 5 onore erat 15 15 LZ 5 16 1 8 Expected End Product and Other Deliverables 1 16 2 Design oe pei sin e QN EORR EH DE RUN ENDE TID ANTA KK I DI QUIDNI ETE 17 2 1 Functional Requirements Fee Y e39 PES ERN RESP PIS NES Y UTER YS PEN EU SEMD VE SVH PARES VUE 17 2 2 Non Functional Kequiremends ice enccsseennuckecuhnucex kun Cua E EN Ky ACER EG Ya nnn 18 2 3 Technology Requirements 4 252 nhat rid eag r eva adve eFo n 2E dera Dn Ra Pak 18 3 Approach and Product Design Results eee esee ee ee eee eee ee ee ee seen nose tna 19 3 1 Overall Bear Tracking Structure eee ee eee eee sesso se sese sesso setae 19 3 1 1 Co
2. 00010203 04 05 06 07 08 09 10 Figure 45 Antenna 2 S11 Parameters The antennas were very sensitive to movement and any adjustment in curvature would affect the S11 parameters of the antenna At the angle that the antenna will be on the bear s collar there were the distinct frequencies as displayed in the above graph New antennas were constructed to better meet the required frequency The new antenna is trimmed in length to adjust the tuned frequency of the system at 217 0375MHz The following antenna had a small coax portion and then a length of 21 cm This antenna had a nice bandwidth around the necessary frequency 1 Start 300 kHz IFBW 70 kHz Stop 1GHz Figure 46 Finalized Antenna S11 Parameters Wireless Bear Tracking Group May1010 Page 112 6 3 Google Maps During the testing of this code it initially let the user input coordinates so that it was able to verify the correct format of the URL implant and the launching of the browser Once the formatting of the URL was correct we set up a communication link with Putty Putty is an open source terminal emulation application that can act as a client for a number of computing protocols To simulate GPS coordinates we set up the PIC to continually output the same string of fake coordinates This was to ensure our port parameters were set up correctly to allow for communication via USB Once we knew what COM port we were commu
3. r Em 59 63 3 10 1 Nickel Metal Hydride 1 63 3 10 2 Taba a E EDEN UA 64 3 10 3 BT CHORI feed 64 A cc 65 cac 65 4 1 1 Printed Circuit Board 65 4 1 2 Paopulated 67 4 1 3 ADE 7021 Register Configuration 67 Wireless Bear Tracking Group May1010 Page 4 4 1 4 Matching ai 80 MEE rivi m 82 AL qoderal Inductor d ca 82 422 PIC Connection to Transceiver 83 4 2 3 Transceiver External pu 83 Lor EE Qc 84 423a POWE RE T 84 4 20 Anteni POE Ie TG 84 LM MES D DII e
4. 113 6 4 Specific Absorption Rate eee eee eese eese sese 113 7 Recommendation for Project Continuation 1 21 eese 114 7 1 Recommendations 114 7 2 Power Section Recommendations eere esee eee eene testen 114 7 3 USB Section Recommendations ccc cscsessosssecssessesssovssesssonssesseossocessceesssessoassncseosssesss 114 74 GPS Section Recommendations ccccerssasscesssovseossssocesonssvosonsssenesonsensvenscaseneseaseeenessos 115 7 5 General Design Recommendations csscccsssccssssccssssccssscccssscccssscccssscscssssscssscsees 115 Wireless Bear Tracking Group May1010 Page 5 8 Statement of sana e sa Se bosse oaa ab od 116 8 1 Task 1 Problem Definition csiccscesciecssesscessconcsossensedadscnsasssocsascsessonsvensoenscesssescassoaseseses 117 8 2 Task 2 Technology Research and Selection 117 8 3 Task 3 End Product Design esesooessccssscessccsscocescosscocesscessecesocesoosssoessocessecssocssceosess 119 8 4 Task 4 End Product Prototype
5. Receive 0 1 3 4 VHF Antenna The antenna design at the collar and base station is very important in order for the signals to be transmitted at the distances necessary for the bear tracking system The collar and the routing unit will both have different antenna types and styles due to the different restrictions The combination of the two antenna types should have a transmission distance in the wooded landscape of nearly five miles The antenna at the collar is very restricted in size and shape The antenna must fit on the collar and be able to withstand the bear s abuse The antenna should be sewn into the collar as much as possible and if it protrudes it must be very minor as to avoid damage by the bears Curvature of the antenna around the collar and proximity to the bear will greatly affect the performance of the antenna Wireless Bear Tracking Group May1010 Page 42 The router antenna can be much more sizable which will also allow for a larger antenna gain It is necessary in order to receive the signals sent by the collar antenna which may be restricted due to different obstructions It can be assumed that the router will be placed in a relatively clear and higher elevated location Wireless communication can be summed up in the following equation sometimes called the link equation or link budget equation 4 42 Pp R TATUR Y B The and Pg are the power transmitted and the power recei
6. 1 1 1 lt 119 8 5 Task 5 End Product Testing 120 8 6 Task 6 Presentations 121 8 7 Task 7 Product Documentation ssesessoesooesoesoescoesossoessoesoosseesoesoossoesoesoossoesoesoossosee 121 9 Resourcesand MU UE PN CR HER XN 9 HF 123 SX MEM o e M M 123 Lc dil 124 T0 Closure aio chia nanan mi a oU ERE REP RR EAE 126 10 1 Project Contact Informatblofi Een phi a i od nets eoe poa iD 126 102 Closmg SUMMArY YER EExFONE isise e esM DRE OE 127 Wireless Bear Tracking Group May1010 Page 6 List of Tables Table DescHDHUODS 33 Table 2 Timing Table for ADF7021 Analog Devices 2009 2 2 2 2 34 Table 3 RF Switch Control DIOS 42 Table 4 Nema Case Standards Computer Dynamics eee 56 Table 3 Power Requitemellls 57 Table 6 ilc e M M 66 Table 7 TX quac m a 68 Table 8 TX Resister OY ANC m
7. 85 DESEE 85 A c 86 5 System and Unit Level Test ee eee seen sese snos esses eee eo se eto 101 5 1 Transceiver Unit Level Test Cases crecer eee eene n etna aano 101 5 2 VHF Antenna Unit Level Test Cases 101 5 3 GPS Module Unit Level Test 866 6 5 T NP n IS ERN Y 102 5 4 Microcontroller Unit Level Test Cases scsssessosssensocasssnssosssescosesesessosassvossesstensonsee 102 5 5 Chassis Unit Level Test Cases scsicsccscsccscccsscoscneccessctsescssisseossnssssssousecncnsiccescasscasssntencsen 103 5 6 Battery Unit Level Test Cases ccssassssssossssesssesesnssvosssesoosvsenssvovvossesssssessessneesseesensees 103 5 7 Power Supply Circuit Unit Level Test 4 0 103 5 8 System Test 68 EN ENSURE E o 104 6 System and Unit Level Test Case Results e eee ee eee eee ee eee eee eee eee 106 6 106 MEN VIP 111 6 3 Goosle
8. unsigned char gps read unsigned char rdptr unsigned char length of string 2 unsigned char length high length low length gps write loop will continue to address the GPS until ack and then will address the for Write load address of the bytes available OxFD WriteI2C1 OxFD WRITE address to GPS IdleI2C1 ensure module is idle gps read loop will continue to address the GPS until ack and then will address the for Read getsI2Cl length of string 2 read in string of the length of the string in memory NotAckI2C1 send not ACK condition while SSP1CON2bits ACKEN wait until ACK sequence is over StopI2C1 send STOP condition while SSPICON2bits PEN wait until stop condition is over length high length of string 0 length low length of string 1 if length high gt 1 Wireless Bear Tracking Group May1010 Page 202 length OxFF length length low gps read loop will continue to address the GPS until ack and then will address the for Read getsI2Cl rdptr length read in multiple bytes NotAckI2C1 send not ACK condition while SSP1CON2bits ACKEN wait until ACK sequence is over StopI2C1 send STOP condition while SSPICON2bits PEN wait until stop condition is over return length Function gps write Params dataptr Character type pointer to data to write length Number of bytes to write to I2C device
9. 68 Table 9 TX Resister ia ED ors 70 Table 10 NOR UM IRI ti hai e a au Yacht Patti dnm asd Unde lau 71 Table 11 TX Register 2 Value M B 71 a EE MOD Pd FE FOR NUM RIDE 72 Table 13 TX Bit Lalernoy 73 Table 14 TX Register power down Vallae exu street to m cte 73 Table 15 RX Register 1 val e iiie e teet oue eda Oase oM ie eid 74 Table T8 BA Register vali ies dei ettet dU Padi Mu basi 74 Table 17 EX Register D Vale iu aie ende toe tei ei ta epu 74 18 RX Regist r 5 rl E 75 Table 19 RX Register NRI c 76 Table 20 RX uae c rcm 27 Table 21 EA Register value iure Een ta eii 77 Table 22 RX Register 4 TI Table 237 RX 79 Table 24 Gain Mode Correction Analog Devices retener ont toon 92 Table 23 4B 5B Encoding Mp PN 99 Table 26 Packet Format Size Before Encoding uiuo etre 100 Table 27 Tasks to be
10. 116 Table 28 Single Unit Estimated 123 Table 123 Wireless Bear Tracking Group May1010 Page 7 List of Figures Figure L VHF UHF iais 17 Figure 2 Network Example ie re oreet esii aniis eM ua 23 Figure 3 TDM General 24 Figure 4 Time Slot ASS mie a 28 Ligure 5 System esatto te 32 Figure 6 Interface of Transceiver RF Switch to Microcontroller esses 33 Figure 7 Timing Diagram for Writing to ADF7021 Registers Analog Devices 34 Figure 8 Timing Diagram for Readback Analog Devices see 35 Figure 9 Transmit sequence after power up Analog Devices 2009 36 Figure 10 Receive sequence after power up Analog Devices 2009 37 Figure 11 RF Output Matching Wet yr cscs ccs 39 Figure 12 RF Output Matching Network Simulation 39 Figure 13 RF Input Matching Network Usern nal dbz Dd Etpa Dd ieee GR enar an 40 Figure 14 RF Input
11. Vin 6 fsw 200e3 am L 0 1e 6 100e 6 x Vout5 5 PUE d Iripple5 Vin Vout5 L l fsw i Vogt3 Vvin asp QUET ESR5 25e 3 Iripple5 d 7 plot L ESR5 p xlabel Inductor Value uH ylabel ESR Ohm d Figure 28 5V ESR Calculations From the graph above it is shown that selecting a 47uH inductor will result in the choice of capacitor having an ESR of about 282mQ After much research it was found that the best choices were a 47uH inductor and a 47uF tantalum capacitor with 300m ESR The inductor chosen must be able to handle the proper current draw The 5V supply is estimated to draw up to 330mA For worst case scenario we will assume the regulator draws 120mA According to the ADP3050 datasheet the inductor must be able to handle 20 more than the peak switching current The calculations for this are shown below 1 Isw pk Iout max 2 lripple 330mA 0 5 x 337 5mA 0 49875A 1 20 x Isw pk 1 20 x 0 49875 0 5985A where Isw pk is the peak swing current Iout max is the expected maximum output current and Iripple is the output ripple current After much research it was found that a 47uH inductor with 600mA current rating was sufficient 3 9 3 4 Final Power Circuit As stated before three regulators provide three different power lines The 3 3V ALWAYS line powers the Microchip PIC18F46J11 as well as the backup voltage for the GPS unit This l
12. void eusart2_init byte mode if mode 1 SPBRG2 25 Baud rate 25 2400 baud Use SYNC 0 BRGH 0 BRG16 0 to determine SPBRG2 if mode O SPBRG2 207 Baud rate 207 2 300 baud Use SYNC 0 BRGH 0 BRG16 0 to determine SPBRG2 Keep below 9600 for an accurate reading BAUDCON2bits TXCKP 0 TXSTA2bits SYNC 0 Required for TX RX setup TXSTA2bits TXEN 1 enable transmission RCSTA2bits SPEN 1 Required for TX RX setup PIE3bits TX2IE 0 No transmission interrupts PIE3bits RC2IE 1 Set receive interrupts IPR3bits RC2IP 1 set receive interrupt as high prioity INTCONbits GIEL 1 Enable global low priority interrupts INTCONbits GIEH 1 Enable global high priority interrupts RCSTA2bits CREN 1 RX setup TRISCbits TRISC6 1 Set RX pin as input TRISCbits TRISC7 0 Set TX pin as output return Sets up the registers of the pic to be used for Syncrounous TX RX void syc eusart2 init byte mode if mode 1 TX MODE TRISCbits TRISC7 1 Set CLK pin as input TRISCbits TRISC6 0 Set TX pin as output BAUDCON2bits TXCKP 0 1 noninverted 0 inverted TXSTA2bits SYNC 1 Synchronous mode RCSTA2bits SPEN 1 Enables serial port TXSTA2bits CSRC 0 Slave mode RCSTA2bits CREN 0 disables continuous receive RCSTA2bits SREN 0 don t care PIE3bits TX2IE 0 No transmission interrupts TXSTA2bits TXEN 1 enables transmission
13. Frames divided into time slots Each user is allocated one slot Time slots contain data 10101010111010101 with a guard period if needed for syncronisation Source www wikipedia org Guard periods optional Figure 3 TDM General Diagram This model assumes that a connection has been previously established and time slots have been assigned to each user Connection establishment and time slot assignment will be discussed later in this section Wireless Bear Tracking Group May1010 Page 24 3 2 3 3 General Network Structure Consider again the example network shown in Figure 2 where nine users have data routed to home base by three different routers In this system all routers are constantly listening and do not turn off or sleep The units only turn on when it is their turn to speak The unit will know when its turn to speak is based on the time slot given This timeslot or specified amount of time where only one particular unit speaks is given to the unit prior to shipment and is hardcoded To determine the number of time slots available the following equation can be used TS baud g where TS is the number of time slots baud is the bit rate bits per second bpTx 18 the number of bits per transmission needed t4 is the time needed for data transmission in seconds and t is the guard period as shown in the previous diagram two guard periods are needed one at the b
14. RX 3 lt lt 4 amp 0x1F lt lt 16 lat6 decode message RX 3 gt gt 1 amp 0x1F lt lt 20 lat7 decode message RX 3 gt gt 6 RX 4 lt lt 2 amp 0x1F lt lt 24 lat8 decode message RX 4 gt gt 3 amp 0x1F lt lt 28 lat latl lat2 lat3 lat4 lat5 lat6 lat7 lat8 return lat Decodes the longitude data from the encoded shifted packet signed long rx decode lon unsigned char RxX long latl lat2 lat3 lat4 lat5 lat6 lat7 lat8 lat 0 lati decode message RX 5 amp 0 1 lat2 decode message RX 5 gt gt 5 RX 6 lt lt 3 amp 0Ox1F 4 lat3 decode message RX 6 gt gt 2 amp OxlF 8 lat4 decode message RX 6 227 RX 7 lt lt 1 amp 0x1F lt lt 12 lat5 decode_message RX 7 gt gt 4 RX 8 lt lt 4 amp 0x1F lt lt 16 lat6 decode message RX 8 gt gt 1 amp 0x1F lt lt 20 lat7 decode message RX 8 gt gt 6 RX 9 lt lt 2 amp 0x1F lt lt 24 lat8 decode message RX 9 gt gt 3 amp 0x1F lt lt 28 lat latl lat2 lat3 lat4 lat5 lat6 lat7 lat8 return lat Decodes the time from the encoded shifted packet unsigned long rx decode time unsigned char RX long lati lat2 lat3 lat4 lat5 lat6 lat7 lat8 lat 0 latl decode message RX 10 amp Ox1F lat2 decode message RX 1
15. Some messages do not default output to the data stream This function will take a class and id of a message and have that message type be output to the stream each time it is available 4 3 2 8 5 ubx cfg inf off The UBLOX has many different error messages available to send to the PIC This function turns off all information messages including errors and warnings 4 3 2 9 Packet Formatting 4 3 2 9 1 Preamble The preamble consists of a series of 48 alternating 1 s and 0 s This is required by the VHF transceiver in order to lock on to the signal Wireless Bear Tracking Group May1010 Page 98 4 3 2 9 2 Start bit The start bit that we used is OXBA OxD5 This is the signal that the information is about to be sent so the receiver can be ready to receive the data 4 3 2 9 3 Information For the actual information contained in the packet we included Longitude Latitude Time Status and a Bear ID number 4 3 2 9 4 Encoding For the encoding of the message itself we decided to use 4B 5B encoding This would eliminate the issue of having any series of eight 1 s or eight 0 consecutively The problem with having eight 1 s or eight O s consecutively is that the transceiver can lose the lock on the signal While other encoding methods would have worked as well we decided to use 4B 5B because of its simplicity This functionality uses Table 25 to assign 5 bits of encoding to every 4 bits of data 0 1 2 3 4 5 6
16. This function should be run through a while 1 loop to constantly check for user interaction A user will open a HyperTerminal and set it up to connect to the proper COM port with 2400 baud In the terminal the user will type without quotations and the PIC will print a welcome string as well as a set of choices to the terminal The user will choose a command and based on that choice the PIC will make decisions and perform the required actions 432 52 330 This function is called if the user selects the 3 3V Line On or 3 3V Line Off choice This function turns the 3 3V power line on or off 43 253 chk 50 This function is called if the user selects 5V Line or 5V Line Off choice This function turns the 5V power line on or off 4 3 2 5 4 chk eeprom This function is called if the Status choice is selected Once implemented this function will check the status of the EEPROM chip and report back to the user on its findings 4 3 2 5 5 chk gps This function is called if the GPS Status choice is selected Once implemented this function will check the status of the GPS chip and report back to the user on its findings 4 3 2 5 6 chk trx This function is called if the Transceiver Enable or Transceiver Disable choice 16 selected This function enables or disables the transceiver Wireless Bear Tracking Group May1010 Page 94 4 3 2 5 7 chk
17. initiate START condition while SSP1CON2bits SEN wait until start condition is over Address the UBLOX for a write 0x84 lt 7 1 gt are default 0x42 0 is 1 for a read WriteI2C1 0x85 Address the UBLOX IdleI2C1 ensure module is idle bit SSP1CON2bits ACKSTAT return Wireless Bear Tracking Group May1010 Page 204 Function get gps data Params gpsdata Array of UBX NAV PLLH message Returns 1 if message contains valid data at correct accuracy 0 if message timed out and contains no data Description Loops a read to the UBLOX GPS so that the PIC buffer does not fill and waits for a valid UBX NAV PLLH message Also waits to message at correct accuracy and outputs a valid bit unsigned char get gps data unsigned char gpsdata unsigned long accuracy unsigned char valid 0 Have the function time out if no valid data is found for about 2 minutes unsigned char time out 0 unsigned char class unsigned char id signed long longitude unsigned long accuracy msg unsigned char valid msg Continue to loop until a valid GPS message was received while valid 0 amp amp time out 250 Read the buffer from the UBLOX gps read gpsdata Delay so that the PIC I2C buffer does not overload DelaylOKTCYx 120 Tests to make sure message received has a UBX header valid msg valid ubx msg gpsdata if valid msg 1 Check the class and header
18. Parameter Limit at Tum to Tmax Unit Test Conditions Comments t gt 10 ns SDATA to SCLK setup time b gt 10 ns SDATA to SCLK hold time gt 25 ns SCLK high duration ts gt 25 ns SCLK low duration ts gt 10 ns SCLK to SLE setup time te gt 20 ns SLE pulse width ts 25 ns SCLK to SREAD data valid readback to lt 25 ns SREAD hold time after SCLK readback tio gt 10 ns SCLK to SLE disable time readback Table 2 Timing Table for ADF7021 Analog Devices 2009 i i i here hu 1 1 1 1 w ee l DB1 DBO LSB SDATA 0831 MSB mE m CONTROL BIT C2 CONTROL BIT C1 1 ste I f f 1 I 1 1 SLE 5 Figure 7 Timing Diagram for Writing to ADF7021 Registers Analog Devices Readback from the ADF7021 can be performed to read back the follow seven values AFC RSSI battery voltage temperature external ADC filter bandwidth calibration and silicon revision To read back this data the readback enable bit in register 7 must be set to 1 SLE must go high to write the data to register 7 The data appearing one clock cycle after SLE goes high must be ignored After this ignored clock cycle the valid data will appear starting with the most significant bit bit 15 After bit 0 has been read one clock cycle should pass before setting SLE low to allow for the SREAD pin to be set back to tris
19. Radiometrix UHX1 operated at a frequency of 140 to 175 MHz and allowed output power of 1 mW to 500 mW It used FM modulation with channel spacing of 12 5 and 25 kHz The temperature rating on the device was from 30 to 75 With the temperature only going down to 30 choosing to use the 216 to 220 MHz band and a cost of 266 this transceiver was not a valid option Melexis TH7122 transceiver allowed frequency range of 27 to 930 MHz It is digitally programmable with modulation schemes of FSK FM and ASK The chip has an adjustable output power of 20 to 10 dBm which means that an external power amplifier Wireless Bear Tracking Group May1010 Page 30 would be needed to achieve an output power of 1 watt The transceiver has an operating temperature range of 40 to 85 and can transmit at a data rate as low as DC with external components and as high as 20 kbps Narrowband operation required more external components to improve performance TH7122 had a sensitivity of 107 dBm and had a cost of 13 40 The last transceiver we considered was Analog Devices ADF7021 The ADF7021 had a frequency range of 80 to 950 MHz It is digitally programmable with modulation schemes of FSK 3FSK 4 5 and MSK The chip has an adjustable output power of 16 dBm to 13 dBm which means that an external power amplifier would be needed to achieve an output power of 1 watt The transceiver has an operating temperature range of 40 to 85 C and can t
20. 7 Wait 40 us 8 Write to Register 2 Transmit Modulation Register Oo202020 Table 10 VHF Muxout Settings REGULATOR READY DEFAULT FILTER CAL COMPLETE DIGITAL LOCK DETECT RSSI READY Tx Rx LOGIC ZERO TRISTATE LOGIC ONE 0 10 00100 1110 100100 11 011 0 000 0010 Raised Tx Data Tx Faev 78 PA PA PA PA Modulation Address Cosine Invert output Bias Ramp Enable Scheme Alpha Inverted power 11 64 Off 0 2FSK Default Data 36 uA codes bit Table 11 TX Register 2 value If the power amplifier PA is enabled disabled by PA_Enable it ramps up at the programmed rate but turns off hard If the PA is enabled disabled by Tx Rx RO_DB27 it ramps up and down at the programmed rate PA Ramp prevents spectral splattering or spurs in the output spectrum By gradually ramping the PA on and off PA transient spurs are minimized Setting to 64 codes per bit which is approximately 1 300 3 33 ms ramp time Less codes per bit causes a more gradual ramp PA Bias current is recommended to be 11 uA when power greater than 10 dBm is required Wireless Bear Tracking Group May1010 Page 71 The external power amplifier has gain between 19 and 24 dB at our current frequency with a 1 db compression point of 29 5 dBm The internal power amplifier is set by writing the corresponding value seen in Table 12 PA output power into register two P2 P1 PA LEVEL
21. IF Cal Lower Tone Divide and IF Cal Upper Tone Divide are given by the following formulas XTAL 5 8 kHz IF _CAL_LOWER_TONE _ DIVIDE x2 8 131 5kHz IF CAL UPPER TONE _ DIVIDE x 2 Analog Devices In our case IF CAL LOWER DIVIDE and IF CAL UPPER TONE DIVIDE should be 31 and 15 IF Tone calibration Time is recommended to be at least 500 us which is given by the following equation IF CAL DWELL TIME SEQ CLK IF Tone Calibration Time Analog Devices The SEQ is equal to 100 8 kHz which is given in Register 3 which makes the IF CAL DWELL TIME to be at least 51 to have at least a 500 us calibration time The total time for a fine IF filter calibration is IF Tone Calibration Time times 10 which is around 5 06 ms 7 Write to Register 5 IF Filter Setup Register 0 00000 0 0000 000000 001010001 1 0101 IR IR IR IR IF Filter IF Filter IF Cal Address Gain Gain Gain Phase Phase Adjust 0 Divider 81 Coarse Do Adjust Adjust Adjust Adjust Adjust Calibration UP DN Mag I Q Mag Table 18 RX Register 5 value Register 5 sets up the Coarse calibration Wireless Bear Tracking Group May1010 Page 75 IF Filter Divider is given by the following equation which value of 81 gives us the closest value to 50 kHz XTAL IF FILTER _ DIVIDER Analog Devices IF Filter Adjust is automatically adjusted when
22. Wireless Bear Tracking Group May1010 Page 155 else if mode 2 RX Mode These settings are used for Ayscrounous Transmission and are not need at this time for Syncrous transmission TRISCbits TRISC7 1 Set CLK pin as output TRISCbits TRISC6 1 Set RX pin as output BAUDCON2bits RXDTP 0 received data is inverted from transciever active low TXSTA2bits SYNC 1 Synchronous mode RCSTA2bits SPEN 1 Enables serial port TXSTA2bits CSRC 0 Slave mode PIE3bits RC2IE 1 Set receive interrupts IPR3bits RC2IP 1 set receive interrupt as high prioity INTCONbits GIEL 1 Enable global low priority interrupts INTCONbits GIEH 1 Enable global high priority interrupts RCSTA2bits CREN 1 enables continous recieve mode These settings are used for syncrounous transmission TRISCbits TRISC7 TRISCbits TRISC6 1 Set CLK pin as input 1 Set RX pin as input INTCONbits GIE 1 enable global intrrupts INTCONbits PEIE 0 disables perpheral interrupts INTCON2bits INTEDG1 1 INT 1 rising edge INTCON2bits INTEDG2 1 INT 2 rising edge INTCON3bits INT1IP 1 INT 1 High prioity INTCON3bits INT2IP 1 INT 2 High prioity INTCON3bits INT1IF 0 INT 1 Flag clear INTCON3bits INT2IF 0 INT 2 Flag clear INTCON3bits INT1IE 1 INT 1 Enable INTCON3bits INT2IE 0 INT 2 Disables This gets enabled when SYNC word is detected initizlies global variables
23. m3 m2 freq 217 freq 217 0MHz m1 real Zin1 OM 182 imag Zin1 0 215 freq 217 0M Hz dB S 1 1 2 51 032 19 10 10 ex m3 om ec s i 5 mm 0 1 lt a 100 8 10 16 20 21 20 2 2 10 186 20 21 20 260 2 freq MHz freq MHz Figure 14 RF Input Matching Network Simulation Wireless Bear Tracking Group May1010 Page 40 3 3 8 9 ADF7021 Simulation Using ADIsimSRD Design Studio provided by Analog Devices simulations were performed to simulate the performance of the transceiver s output using the values of the loop filter oscillator and 50 ohm load The results of these simulations can be found in Figure 15 Modulation Domain Analyzer Spectrum Analyzer aus LC le 10 9 0 z ts 204 4 1 6 1 5 5 5 9 8 E diee A E uc 5 i 40 m 1 1 802 50 40 30 20 10 0 10 20 30 40 50 Frequency kHz Centre Frequency 217 0375MHz RBW 100Hz Span 100kHz Detector Peak Max Hold over 256 traces Open Loop Gain at 217 0375MHz 100 180 1 10 100k 1M 10M Frequency Hz Phase Noise at 217 0375MHz e0 E 70 i 1 Loop Filter ET ordeesus Chip 1 Ref E apa vco 100 i gt a 110 2 H 120 8 i a 130 zn d i 150 soho i 160 i 1k 10k
24. 0 01 set rate to one to send message everytime the message is available Wireless Bear Tracking Group May1010 Page 210 Function ubx cfg inf off Params void Returns void Description Disable all warning and INFormation messages void ubx cfg inf off void See page 93 of the Protocol Specification Document char CK A CK B int Inc unsigned char length 24 payload 8 unsigned char message 24 UBX message headers message 0 OxB5 message 1 0x62 0 06 Class ID 0x02 Message ID message 2 message 3 Payload Length Little Endian message 4 0x10 message 5 0x00 message 6 0x00 Configure UBX Messages message 10 0x00 Disable all messages message 11 0x00 message 12 0x00 message 13 0x00 message 14 0x01 Configure NMEA Messages message 18 0x00 Disable all messages message 19 0x00 message 20 0x00 message 21 0x00 Check Sum Fields CK 0 CK B 0 for Inc 2 Inc lt length 2 CK A CK message Inc CK B CK B CK A message length 2 message length 1 CK A CK B gps write message length return Wireless Bear Tracking Group May1010 Page 211 Appendix 27 PIC Code ublox cfg h ifndef UBLOX H_ define UBLOX H_ Page 91 CFG MSG Sets how often a message is sent to the GPS Module Settings For example how often do we need to send a GPS messa
25. 0 PA OFF 1 16 0 dBm 2 3 63 13 dBm Table 12 PA output power The estimated power output at the SMA connector can be given by the following equation Output Power in dBm 0 467742 Level 0 7323 Loss in Circuit in dBm The output power should not exceed more than 29 dBm to avoid non linearity The desired frequency deviation is 4 80 kHz This frequency deviation allows us to stay in the 25 kHz channel and allows the spectrum output to drop off This frequency deviation was also calculated by ADIsimSRD based on the channel width and the baud rate The frequency deviation is given by the following formula from the datasheet Frequency Deviation Hz Tx FREQUENCY DEVIATION x PFD 316 Analog Devices By setting TX FREQUENCY DEVIATION to 78 it gives us a frequency deviation of 4 798 where frequency is 4 032 MHz given in Register 1 data is set to be inverted because in receive mode the transceiver needs to be set to be inverted to correctly set the correlator Thus to have the PIC receive non inverted data we are inverting the data when we send it 9 Wait at least 3 33 ms Wireless Bear Tracking Group May1010 Page 72 10 Transmit Data 11 Wait 3 4 ms before power down The delay is needed because of bit latency as shown in Table 13 A latency of 1 bit means that 1 bit rate should be waited before powering down In this case it is 1 300 which is 3 33 ms Modulation
26. Federal Communications Commission Part 90 Title 47 Telecommunication Part 90 20 February 2009 Federal Communications Commission 29 November 2009 http www access gpo gov nara cfr waisidx 08 47cfr90 08 html Gulley Walter R Construction Details for a GPS Helix Antenna 29 November 2009 lt http www ggrweb con article gulley html gt LandAirSea 30 September 2009 lt http www landairsea com index html gt Mehaffey Joe GPS Antennas for Consumer GPS Receivers Which type is best 29 November 2009 lt http www gpsinformation org joe gpsantennaspecs htm gt Saunders Simon R and Alejandro Aragon Zavala Antennas and Propogation for Wireless Communication Systems Second Edition Chichester England John Wiley amp Sons Ltd 2007 Setian Leo Practical Communication Antennas with Wireless Applications Upper Saddle River Prentice Hall PTR 1998 Telonics 30 September 2009 lt http www telonics com products vhfStandard MOD 500 php gt Wireless Bear Tracking Group May1010 Page 128 Appendix 1 Operations Manual Done by Joe Lane Operation Manual of the System Senior Design 401 Joe Lane April 23 2010 Project title Wireless Mesh Bear Tracking Project team Zach Bruce team leader Blane Chesnut Webmaster Chris Donnelly John Pritchard Communications Liaison Adam Rasmussen Dr Ahmed E Kamal Advisor Mark Tekippe Digi International Client 1 High level Objective Wireless
27. Previously three buck converters were used in the power section for a 3 3V always power line a 3 3V selectable power line and a 5V selectable power line The purpose for using buck converters was to allow for an efficient step down from the 6V battery supply as well as a wide range of input voltages for when a wall transformer is used This proved to be a waste of space for only a small save in efficiency as well as an expensive alternative The new design replaces these buck converters with selectable LDO regulators Very few components are need for these supplies and their efficiencies are comparable to the buck converters at the input voltages being used They are also much less expensive 7 3 USB Section Recommendations For the USB section in the previous design an FTDI chip was used for USB to serial conversion This was an excellent choice for its capabilities but it still took up a lot of space and used several components A new chip the Silicon Labs CP2102 is now used costing the same amount but having a smaller package size and requiring less external components This will again save board space and cost Wireless Bear Tracking Group May1010 Page 114 7 4 GPS Section Recommendations The NEO 5Q GPS chip is replaced with the EM 408 module and antenna package Instead of being integrated into the board as before this module will plug into a connector mounted on the board and be a completely separate entity This module greatly
28. for i2c instead of SPI 55 1 1 5 55 1 1000 I2C Master mode clock SSPICON1bits SSPM3 1 SSP1CON1bits SSPM2 SSP1ICON1bits SSPM1 SSPICON1bits SSPMO FOSC 4 SSPxADD 1 0 0 0 Set I2C clock to 100 KHz ADD 0 09 Set I2C clock to 31 25 KHz ADD 0 1 SSPlADD 0 1 SSPISTATbits SMP 1 Slew Rate control Must be 1 At a value of zero the clock edges have a higher slew rate and the UBLOX has difficulty processing them Turn off various NMEA strings cfg msg off OxF0 0x03 Turn off GSV cfg msg off OxF0 0x04 Turn off RMC cfg msg off OxF0 0x02 Turn off GSA cfg msg off OxF0 0x00 Turn off GGA Wireless Bear Tracking Group May1010 Page 201 ubx cfg msg off OxF0 0x01 Turn off GLL ubx cfg msg off OxF0 0x05 Turn off VTG cfg msg off OxF0 0x41 Turn off TXT Turn on NAV POSLLH message all the time ubx cfg msg 0 01 0x02 Turn off all info messages ubx cfg inf off Need to delay in order for the PIC I2c buffer to clear out DelaylOKTCYx 120 return Function gps read Params rdptr Character type pointer to PICmicro MCU RAM for storage of data read from I2C device length Number of bytes to read from I2C device Returns unsigned int number of bytes read Description reads all buffered information from the GPS d
29. n y DPX Spectrum CF 217 0400 MHz Wi dh NOU WM M m Wt NM MAN pn Vio 9 Span 2 580 MHz MR 35 03 dBm 217 03525 MHz 100 0 kHz 9 Span Figure 40 Output Spectrum of board A with transceiver set at level 63 power 13 dBm With the modification to the ground connection of board B we saw the output was attenuated as seen in Figure 41 Figure 42 and Figure 43 When we had the power level of the transceiver at its highest we observed an increase in spectral content as seen in Figure 43 The increase in spectral content may be caused if the power amplifier was not Wireless Bear Tracking Group May1010 Page 108 acting as a linear device We believe that the PA board B is no longer in a state of functionality which is why there is so much attenuation M1 0 13 00 dBm 217 04552 MHz 0 00 dBm M1 56 40 dBm AM1 2 98 dB 217 045512 MHz 9 6 kHz MR 38 76 dBm MR 38 19 dBm 217 03592 MHz A 217 035912 MHz 113 00 dBm Span 30 00 kHz Autoscale 9 CF e J ps o B o S I A 217 04000 MHz Span 30 00 kHz Figure 42 Spectrum of board B with modification and transceiver output power level of 36 0 dBm Wireless Bear Tracking Group May1010 Page 109 gt 0 00 i gt 13 00 Mr 9 dB div 217 04 MHz dB div 217 065 MHz 10 0 dB 10 0 dB RBW EN 1 00 MHz 1 00 kHz VBW n Vat M
30. 0x62 0x06 Class ID 0x01 Message ID message 2 message 3 Payload Length Little Endian message 4 0x03 message 5 0x00 Class and ID of message to turn off message 6 class message 7 id message 8 0x00 set rate to zero to cancel message Check Sum Fields CK 0 CK_B 0 for Inc 2 Inc lt length 2 CK B CK message Inc CK B CK A Wireless Bear Tracking Group May1010 Page 209 CK B message length 2 message length 1 gps write message length return Function ubx cfg msg on Params void Returns void Description Set the rate that a message is polled to high as possible void ubx cfg msg on unsigned char class unsigned char id See page 83 of the Protocol Specification Document char CK A CK B int Inc unsigned char length 11 payload 8 unsigned char message 11 UBX message headers message 0 OxB5 message 1 0x62 0x06 Class ID 0x01 Message ID message 2 message 3 Payload Length Little Endian message 4 0x03 message 5 0x00 Class and ID of message to turn on message 6 class message 7 id message 8 Check Sum Fields CK A 0 CK B 0 for Inc 2 Inc lt length 2 CK message Inc CK B CK B CK A message length 2 message length 1 CK A CK B gps write message length return
31. 100 00 dBm 113 00 dBm 2 225 4 MHz Span 225 4 MHz 2 Span 100 0 MHz Hardware Static Meceanee Figure 43 Spectrum of board B with modification and transceiver output power level of 63 13 dBm Wireless Bear Tracking Group May1010 Page 110 6 2 Antenna The RF transmission of the board was initially tested using a quarter wave coaxial cable to connect the two units After acceptable transmission rate was achieved the quarter wave antennas were used in testing To test the performance of the quarter wave antenna we used a network analyzer to test the reflection S Parameters The antenna had tuned frequencies that were slightly off of accepted and the desired frequency was almost entirely reflected m2 freq 90 7 3MHz dB S 1 1 10 223 m10 freq 216 3MHz dB S 1 1 0 584 m1 freqz27 1 6MHz dB S 1 1 11 493 m3 freq 472 5MHz dB S 1 1 2 3 516 m4 freq 653 4MHz 5 1 1 5 946 dB S 1 1 Input Reflection Coefficient 0 0 0 2 0 4 0 6 0 8 1 0 freq GHz Figure 44 Antenna A S11 Parameters Wireless Bear Tracking Group May1010 Page 111 Forward Transmission dB m5 m freq 90 73MHz 2 1 1 dB S 2 2 16 534 serj m9 a freq 216 3MHz 64 5 2 2 0 774 1 m6 e 1 freq 256 5MHz 40 l 5 dB S 2 2 10 341 5 4 m7 12 447 4 aa dB S 2 2 2 698 14 m8 Ae TP freq 633 3MHz 1 dB S 2 2 6 838 18
32. Embedded Programming The objective of Subtask 3 2 is to design the logic and structure of the embedded software We will design the logic structure and necessary configurations needed for our microcontroller on both the unit on the bear and any necessary routers We will also develop the necessary configurations of any other device in our hardware design We will start initial coding necessary to perform part performance testing done in Subtask 3 1 8 3 3 Subtask 3 3 Software Design The objective of Subtask 3 3 is to design the necessary software needed to allow the user to obtain the information from the bears on a computer At the least the software will allow the user retrieve the raw data from the bear on a computer If time allows more sophisticated software may be developed to map the data of each bear on a map 8 3 4 Subtask 3 4 Chassis The objective of Subtask 3 4 is to design the physical layout of the chassis of the unit on the bear and any necessary routers We will also determine how and where we will be making the chassis 8 4 Task 4 End Product Prototype Development The objective of Task 4 is to build the necessary prototypes At the end of this task we will have created multiple prototypes of our design in Task 3 Wireless Bear Tracking Group May1010 Page 119 8 4 1 Subtask 4 1 Acquire Materials for Prototypes The objective of Subtask 4 1 is to create a list of necessary parts and materials to build t
33. Figure 31 Transceiver output matching network simulation circuit with non ideals 80 Figure 32 Transceiver output matching network simulation with non ideals 8l Figure 33 Transceiver input matching network circuit with non ideals 8l Figure 34 Transceiver input matching network simulation with non ideals 82 Figure 35 RF output vs total external inductance Analog Devices 2009 82 Figure 36 Quarter Wave Antenna rennen 85 Figure 37 Output Spectrum of board with transceiver set at level 1 power 16 dBm 107 Figure 38 Output Spectrum of board A with transceiver set at level 36 power 0 dBm with que EJ M 107 Wireless Bear Tracking Group May1010 Page 8 Figure 39 Output Spectrum of board with transceiver set at level 36 power 0 dBm with Span 2 0 MHZ NT TT S 108 Figure 40 Output Spectrum of board with transceiver set at level 63 power 13 dBm 108 Figure 41 Spectrum of board B with modification and transceiver output power level of 1 16 dil 109 Figure 42 Spectrum of board B with modification and transceiver output power level of 36 0 ii m T H Rm 109 Figure 43 Spectr
34. Returns void Description write a CFG message to the UBLOX void gps write unsigned char message unsigned char length unsigned char k byte gps write loop will continue to address the GPS until ack and then will address the for Write for k 0 k lt length byte message k WriteI2Cl byte Write data byte to UBLOX IdleI2C1 ensure module is idle StopI2C1 send STOP condition while SSP1CON2bits PEN wait until stop condition is over return return Function gps write loop Params void Wireless Bear Tracking Group May1010 Page 203 Returns void Description poll the gps chip to see if it is busy and then send a write message void gps write loop void unsigned char ack bit 1 while ack bit 1 IdleI2C1 ensure module is idle StartI2C1 initiate START condition while SSP1CON2bits SEN wait until start condition is over Address the UBLOX for a write 0x84 lt 7 1 gt are default 0x42 lt 0 gt is 0 for a write WriteI2C1 0x84 Address the UBLOX IdleI2C1 ensure module is idle bit SSP1ICON2bits ACKSTAT return Function gps read loop Params void Returns void Description poll the gps chip to see if it is busy and then send a read message void gps read loop void unsigned char ack bit 1 while ack bit 1 IdleI2C1 ensure module is idle StartI2C1
35. Studio This crystal frequency allowed the transceiver to have the exact carrier frequency of 217 025 MHz and a bandwidth of 25 kHz The crystal oscillator frequency was also chosen because it was an available crystal to buy and gave us the exact carrier frequency when multiplied internally The crystal that was chosen is made by Citizen and has a temperature range of 40 to 85 and a load capacitance of 18 0 pF Two capacitances were needed to be put in shunt with the crystal oscillator to achieve the 18 0 pF load capacitance The value of these two capacitors and C5 be approximate using the following formula CIx C2 C14 C2 Cstray and C are the load capacitors C is the load capacitance specified in the crystal s datasheet and is the total parasitic capacitances on the crystal was estimated at 5 pF Using this value of Cstray and the available capacitor values available for purchase and C2 were picked to be 20 and 36 pF 3 3 3 8 Matching Network The RF output of the transceiver was matched to 50 ohm load impedance From the application notes the input impedance at 220 MHz can be modeled as 159 75 153 16 Using the high pass matching network that was suggested the capacitor and inductor values were found as shown in Figure 11 A 100 0 pF capacitor was placed in shunt with the 3 3 voltage supply to prevent the RF from propagating to the voltage supply The simulation of the
36. The increase in length will also be more cumbersome for the bear to fit in the collar Pros e e 3 4 3 Antenna is easily made Very inexpensive Very flexible around the neck of the bear Has a high antenna gain compared to the wavelength antenna Can match the impedance with discrete components Antenna will protrude out of collar and be subject to damage by the bears Antenna is not shielded properly and will also accept a lot of noise The curvature of the antenna will not allow for the ground plane to be perpendicular to the antenna and possibly allow interesting results Research has shown that the ground plane should be several wavelengths long to produce a stable impedance input Sleeve Dipole Antenna The sleeve dipole antenna is the solution to the unwanted noise possibilities involved in an unshielded whip antenna A conductive sleeve surrounds the coaxial transmission line for a certain portion of the antenna The conductive sleeve then connects to the outer shell of the coaxial transmission line and the inner conductor continues as the antenna The length of outer conductor diameter of the conductor and type of dielectric in between the coaxial transmission line and this conductor all affect the antenna This sleeve works to filter out unwanted frequencies Wireless Bear Tracking Group May1010 Page 45 The sleeve dipole antennas available have mostly a hard metal sleeves which make it difficult to wrap around the n
37. i 10 i 0 if j 600 j 0 Avg_AFC 0 for k 0 k lt 1000 k return Wireless Bear Tracking Group May1010 Page 151 ifndef MAIN H define MAIN H_ Appendix 11 PIC Code main h Deep Sleep Watchdog Postscaler 2 DSWDTPS 2 DSWDTPS 8 DSWDTPS 32 DSWDTPS 128 DSWDTPS 512 DSWDTPS 2048 DSWDTPS 8192 DSWDTPS K32 DSWDTPS K131 DSWDTPS K524 7 DSWDTPS M2 DSWDTPS M8 DSWDTPS M33 DSWDTPS M134 DSWDTPS M536 DSWDTPS G2 include p18cxxx h include dpslp h include datatypes h define TRUE 1 define DSPER 32 Function Prototypes void activate unit void the function that activates all peripheral functionality void maintenance void void TX_unit void void RX_unit void void tx_test void void rx_test void 2 2 1 ms 8 8 3 ms 32 33 ms 128 132 ms 512 528 ms 2 048 2 1 seconds 8 192 8 5 seconds 32 768 34 seconds 131 072 135 seconds 524 288 9 minutes 2 097 152 36 minutes 8 388 608 2 4 hours 33 554 432 9 6 hours 134 217 728 38 5 hours 536 870 912 6 4 days 2 147 483 648 25 7 days for demo purposes for demo purposes testing purposes only testing purposes only this is the sleep period postscalar Wireless Bear Tracking Group May1010 Page 152 Appendix 12 Code init c
38. of 6 main sections The PIC microcontroller section has the microcontroller that acts as the main controller of all other systems on the board The EEPROM section has an EEPROM chip to provide extra memory The VHF section controls the sending and recieving of data over the VHF wireless signal The GPS section houses the GPS chip which processes GPS location data The power section handles converting the 6V DC input to the various voltages required by the system com ponents The USB section has a USB controller that allows the PIC to be accessed from a computer team has also written the software for the PIC microcontroller that controls the system software allows the controller to turn power on and off to parts of the board It also controls the wireless transciever and GPS The controller provides an interface through the USB so that a user can issue commands to the microcontroller Currently the power USB PIC and EEPROM sections are working Additional debugging is needed for for transceiver and GPS sections 4 System Setup The following instructions explain how to set up and test the USB interface to the PIC controller Wireless Bear Tracking Group May1010 Page 132 10 11 12 13 14 15 16 5 Start the MPLAB software on the computer MPLAB is the integrated development environ ment for the PIC microcontroller Plug the programmer cable into the board In MPLAB connect to the board by s
39. transmission attempts and will down load all correct information We will test the range of router to router communication in an open area e Information received from another router will be successfully downloaded and concatenated to the information already available This complete information will be readily available for serial download from router Networking Communication Time Division multiplexing will successfully allow the position of a collar unit to be sent to router 1 and this information will successfully be forwarded to router 2 If one collar position is sent to more than one router only one router will send a confirmation ACK to the collar unit e Time Division multiplexing will successfully allow the position of two collar units to be sent to router 1 and this information will successfully be forwarded to router 2 If one collar position is sent to more than one router only one router will send a confirmation ACK to the collar unit e Time Division multiplexing will successfully allow the position of three collar units to be sent to router 1 and this information will successfully be forwarded to router 2 Wireless Bear Tracking Group May1010 Page 104 If one collar position is sent to more than one router only one router will send confirmation ACK to the collar unit e Time Division multiplexing will successfully allow the position of two collar units to be sent to router 1 and one collar unit to router 2 The infor
40. unit void unsigned char valid 0 signed long lat 0 lon 0 latitude and longitude unsigned long time 0 Time in ms of week unsigned char status 0 ID Status byte and ID of unit int k i Configures the PIC for transciver RX mode eusart2VHF remap eusart2 init RX Turns on the 3 3 line and makes sure the 5V line is OFF power 33 power 5 OFF turns on the transceiver and switches the RF switch to RX mode Wireless Bear Tracking Group May1010 Page 148 vhf trx ON Switch ctrl RX Delay to allow the transciever to power up for k 0 k lt 90 k delay for 3 6 ms Configures the receiver to RX mode vhf init RX while 1 configures transciever in RX mode and waits until data is received valid VHF Mode transtt Checks to see if valid data is available 1 Valid data if valid 1 Gets the decoded lat lon time status and ID lat get_lat gets the latitude lon get lon gets the longitude time get time gets the time status get_status gets the status ID get_ID gets the ID sets up the port for USB interface eusart2USB remap eusart2_init USB Sends the Data to the PC for mapping to google maps gps map lat lon Syc eusart2VHF remap eusart2 init RX Jelse errortt if trans 20 trans trans Wireless Bear Tracking Group May1010 Page 149 func
41. 100 120 140 160 180 200 220 240 260 280 300 freq MHz Figure 34 Transceiver input matching network simulation with non ideals 4 2 Hardware Modifications The following section defines the modifications made to the original design post PCB fabrication and the reasons for such modifications 4 2 1 External Inductor L10 The frequency range of the transceiver is determined by an external inductor between pin 44 and pin 46 Figure 35 shows the RF output verses total external inductance between pin 44 and 46 of the transceiver FREQUENCY MHz TOTAL EXTERNAL INDUCTANCE nH Figure 35 RF output vs total external inductance Analog Devices 2009 Wireless Bear Tracking Group May1010 Page 82 The inductance value was given by ADIsimSRD at a value of 38 5 nH based our center frequency of 217 0375 MHz We initially used an inductance value of 39 nH L10 However we were only able to get a max frequency of 200 MHz which meant we needed a smaller inductor In our initial design we did not include the inductance of the traces to get to the desired inductance of 38 5 nH After trying different values of inductance a 30 nH inductor gave us the desired frequency that we need It should be noted that if the PCB layout is changed with respect to L10 the external inductance will change depending on the length of the traces from pin 44 and pin 46 to L10 4 2 2 PIC Connection to Transceiver The PIC has two different connection
42. 17 at int when Of REGULATOR NOTES L2 should bancle peak current of at least 35024 L3 should handle peak current issid least 350mA 3 3V close to C53 PIM d Possible 70 Place close to PIN P Poarible Place cloae to PIN 8 ax 1 10 Poraible 10K Bevel I devel Ei These parta seed be depopulated if external source used ty of the cosnector asd segitive on the outzide of the cosnector The 3 94 Regulator must have an cetpet capacitor that bas an ESR of Tinite leas for 25e pp Vripple GPS Requirement The SV Regulator must have an output capacitor that has s ESR of Misoa leas for 25evpp Vripple Mo requirement but wozld lite for transmitter The 3 34 Always regulator dows not necessarily need an output capac Teat Points are for checking voltage lines Place Test poists near each other with gound test poist for easy testing tor with a low ESR Wireless Bear Tracking Group May1010 Page 138 Appendix 7 Layout Layers Figure 49 Top Copper Layer Wireless Bear Tracking Group May1010 Page 139 e as e Figure 51 Top Solder Mask Wireless Bear Tracking Group May1010 Page 140 Beartrackar Rev A 2 15 10 Senior Dasign 1010 GEtate r21 c27 LN TP30 Lio les 47 4 29 45 C16
43. 36 XTAL POWER DOWN REFERENCE CE LOW CE HIGH WAIT 10ys 1ms REGULATOR POWER UP TYPICAL XTAL SETTLING WRITE TO REGISTER 1 TURNS ON WAIT 0 7 ms TYPICAL VCO SETTLING WRITE TO REGISTER 3 TURNS ON Tx Rx CLOCKS OPTIONAL ONLY NECESSARY IF IF FILTER FINE CAL 15 REQUIRED WRITE TO REGISTER 5 STARTS IF FILTER CALIBRATION WAIT 0 2ms eere CAL OR WAIT 5 2ms COARSE CALIBRA TION FINE CALIBRA TION 1 1 WRITE TO REGISTER 11 SET UP SWD OPTIONAL WRITE REGISTER 12 ENABLE SWD ONLY NECESSARY IF 1 SWD IS REQUIRED WRITE TO REGISTER 0 TURNS ON PLL WAIT 40ys TYPICAL PLL SETTLING OPTIONAL ONLY NECESSARY IF AFCIS REQUIRED CE LOW POWER DOWN Figure 10 Receive sequence after power up Analog Devices 2009 Wireless Bear Tracking Group May1010 Page 37 3 3 3 5 Automatic Sync Word Detection The ADF7021 can be set to detect a user defined sync word which can be 12 16 20 or 24 bits long When the transceiver detects the defined sync word SWD is set high 3 3 3 6 Loop Filter Design The loop filter design from pin 1 to pin 42 was designed using Analog Devices software ADIsimSRD Design Studio This software takes the user inputs of frequency bandwidth and crystal oscillator frequency and automatically calculates the values of the loop filter 3 3 3 7 Crystal Oscillator Design The crystal oscillator frequency was chosen based on the SRD ADIsimSRD Design
44. 7 8 9 A B C D E F Table 25 4B 5B Encoding 4 3 2 9 5 Checksum The checksum is an important piece of information to include in the packet because it allows the receiving unit to check to see if the data it is received is Wireless Bear Tracking Group May1010 Page 99 actually valid To compute the checksum we summed all of the encoded data and then encoded the checks 4 3 2 9 6 Shifting In order to reduce the amount of bytes transmitted it was necessary to shift the data so we could transfer 8 data bits instead of 5 data bits and 3 filler bits 4 3 2 9 7 Sending through Once the packet has been formatted it is ready to be sent This is done with a function that will send the data synchronously 4 3 2 9 8 Decoding Once the data has been received it is necessary for it to be decoded in order to actually read the data and convert it in to useful information Each set of values gets decoded separately Longitude Latitude Time Status and Bear ID The decoding has to take each set of 5 bits decode it to 4 bits then recombine two 2 sets of 4 bits to make a byte Longitude and Latitude are signed long 4 bytes Time is unsigned long 4 bytes Status and Bear ID are unsigned characters 1 byte Longitude signed long 4 bytes Latitude signed long 4 bytes Time unsignedlong 4bytes Status unsigned char 1byte Bear ID unsigned char 1byte Table 26 Packet Format Size Before Encoding 4 3 2 9 9 Che
45. 8 length length 8 Wireless Bear Tracking Group May1010 Page 214 return length Function ubx msg class Params message Character type array of the UBX message read from the NEO 5 Returns Unsigned char of Class Description Returns the class of the message unsigned char msg class unsigned char message unsigned char class class message 2 return class Function ubx msg id Params message Character type array of the UBX message read from the NEO 5 Returns Unsigned char of ID Description Returns the ID of the message unsigned char msg id unsigned char message unsigned char msg id msg id message 3 return msg id Function ubx navpllh get latitude Params message Character type array UBX NAV PLLH message Returns Signed Long of lattitude Description Returns lattitude of the message lowest seven digits are decimal Returns 1 7 signed long navpllh get latitude unsigned char message signed long latitude latitude 0x0000FF amp message 17 latitude latitude 8 latitude latitude 0x0000FF amp message 16 latitude latitude 8 latitude latitude 0x0000FF amp message 15 latitude latitude 8 latitude latitude 0x0000FF amp message 14 Wireless Bear Tracking Group May1010 Page 215 return latitude Function ubx navpllh get longitude Params message Character type array U
46. Bear Tracking Group May1010 Page 194 unsigned int address unsigned char eeprom control high address low address IdleI2C2 ensure module is idle StartI2C2 initiate START condition while SSP2CON2bits SEN wait until start condition is over load EEPROM control byte in buffer lt 7 4 gt 1010 3 address block shown as input to function lt 2 1 gt hardware defined address 00 in this case 0 0 for write eeprom control 0 address block amp 0x01 lt lt 3 0x08 WriteI2C2 eeprom control write 1 byte R W bit should be 0 IdleI2C2 ensure module is idle 1 high byte of address into buffer high address address gt gt 8 amp Ox00FF WriteI2C2 high address write address byte to EEPROM IdleI2C2 ensure module is idle load low byte of address into buffer low address address amp Ox00FF WriteI2C2 low address write address byte to EEPROM IdleI2C2 ensure module is idle WriteI2C2 byte Write data byte to EEPROM IdleI2C2 ensure module is idle StopI2C2 send STOP condition while SSP2CON2bits PEN wait until stop condition is over eeprom ack polling Wait for write cycle to complete return return Function eeprom ack polling Params void Returns void Description poll the EEPROM chip to see if it is busy for a page write void eeprom polling void unsigned char eeprom
47. LATD7 j for k 0 k lt 37 Data Bit LATBbits LATB1 bits 19 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 18 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 17 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 16 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit Wireless Bear Tracking Group May1010 Page 174 LATBbits j for k 0 LATBbits for k 0 k LATBbits jifor k 0 LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATBbits j for k 0 k LATB1 bits 15 for j 0 lt 37 LATB1 lt 37 LATB1 lt 37 LATB1 lt 37 LATB1 lt 37 LATB1 lt 37 LATB1 lt 37 LATB1 lt 37 LATB1 37 LATB1 37 LATB1 37 LATB1 37 LATB1 37 LATB1 37 LATB1 37 LATB1 37 k k Data Bit bits 14 for j Data Bit 0 bits 13 for j 0 k k Data Bit bits 12 for j D
48. Latency 2FSK 1 bit GFSK 4 bits RC2FSK Alpha 0 5 5 bits RC2FSK Alpha 0 7 4 bits Table 13 TX Bit Latency 12 Set Register 0 PA power down 000 0 1 00110101 110 1010 0001 0100 0000 Muxout UART Tx Rx RX Integer N Fractional N 27156 Address Regulator Mode No 1 53 Bits Ready 0 Table 14 TX Register 0 power down value By switching TX RX bit to 1 the power amplifier will ramp down which will minimize spectral splattering as explained in TX Register 2 description 13 Wait at least 3 33 ms This delay allows time for the PA to power down 14 Set VHF_CE to 0 By setting VHF_CE to 0 it will turn off the transceiver 4 1 3 2 Receive Mode The following steps show the order for configuring the transceiver in receive mode 1 Set VHF_CE High Setting the VHF_CE high turns on the transceiver 2 Wait at least 1 1 ms This required delay is necessary to allow the power regulators to power up VHF MUXOUT will be asserted high when the regulators are ready Wireless Bear Tracking Group May1010 Page 73 3 Write to Register 1 VCO Oscillator Register 1 00 0011 0 1 11 00 1 0 0000 001 0001 External VCO VCO Bias RF VCO CP XTAL Bias XOSC XTAL Clock out R Address VCO Center given divide Enable Current 20uA higher Enable Doubler divide Counter bits Yes Nominal from by 2 ON Set to current faster Y
49. Lir 0 123 C17 Figure 53 Top Silk Screen Wireless Bear Tracking Group May1010 Page 141 Figure 54 Bottom Silk Screen Wireless Bear Tracking Group May1010 Page 142 66000000 0066 eooQ 6000 e B a e 95 DRILL CHART TOL Figure 55 Drill Chart Wireless Bear Tracking Group May1010 Page 143 Appendix 8 Revision Schematic muon NOILO23HS 014 HOLOZNNOO Sdd NOILO2US GSn lt trj wn H 2 30g ge upd Aquo aeacdind Wireless Bear Tracking Group 1010 Page 144 Appendix 9 PC Code import os urllib import serial while 1 addr Set up serial port ser serial Serial port 7 baudrate 2400 bytesize serial EIGHTBITS parity serial PARITY NONE stopbits serial STOPBITS ONE timeout None xonxoff 0 rtscts 0 interCharTimeout None addr ser read size 25 addr raw _input nAddress or Lat Long if addr lt gt url if addr 0 center addr replace replace lat lng center split url http maps google com maps q st s lat lng else Encode query string into URL url http maps google com q urllib quote addr amp output js print nQuery s url Get XML location
50. Table 5 e System will successfully power down and suppress all voltages on the bus lines and send flag to microcontroller when power up is complete Wireless Bear Tracking Group May1010 Page 103 5 8 System Test Cases The final deliverables will include two router units and three collar units The following tests will be performed with these completed units Unit System Level Tests e The unit will successfully power down all systems and power up after a predetermined amount of time While the unit is in sleep mode it will consume less power e The unit will successfully power up and gain a GPS signal lock Unit to Router Communication e The router will recognize the unit sending a packet of information and download this information The router will recognize the unit within three attempts by the unit and will download all correct information We will test the range of the unit to router communication in an open area e Inaheavily forested area the router will recognize the unit sending a packet of information and download this information The router will recognize the unit within three transmission attempts by the unit and will down load all correct information We will test the range of the unit to router communication in a heavily forested area Router to Router Communication The router will recognize another router sending a packet of information and download this information The router will recognize the router within three
51. USB not needed dont use as USB CFG TMODE Used when fixed location and used for precise time Page 108 CFG NAVX5 Used to set min max number of satellites for navigation Nery specific settings Page 108 CFG NAV5 Used to make different settings for Navigation probably necessary endif Wireless Bear Tracking Group May1010 Page 213 Appendix 28 PIC Code ublox read c File ublox read c Contains the functionality to read strings from the NEo 5 GPS include lt p18 46j11 h gt The PIC used in final design include lt i2c h gt include gps i2c h include main h include ublox read h Function valid ubx msg Params message Character type array of the UBX message read from the NEO 5 Returns 1 Message is a valid UBX Message 0 Message is not a valid UBX Message Description Read the first two bytes and confirm UBX Message unsigned char valid ubx msg unsigned char message unsigned char valid if message 0 OxB5 amp amp message 1 0x62 valid 1 else valid 0 return valid Function ubx msg length Params message Character type array of the UBX message read from the NEO 5 Returns Unsigned int Description return the length of the message including the header and checksum fields unsigned int ubx msg length unsigned char message unsigned int length length 0 00 amp message 4 OxFFOO message 5 1
52. a purchased unit would also save time and money invested in creating a do it yourself type of antenna Mehaffey Wireless Bear Tracking Group May1010 Page 53 3 6 3 Active GPS Patch Antenna Since a manufactured passive GPS patch antenna was already being considered we also looked at purchasing an active GPS patch antenna Research showed that active GPS antennas have the same physical dimensions as passive GPS antennas Even with this same size since they are powered they can locate satellites quicker than their passive counterparts They can also track satellites better through the dense forestry that the bears in Northern Minnesota habitat Even with the advantages of the active GPS patch antenna the cost is the same as the passive GPS patch antenna also less than 15 per unit 3 6 4 Detailed Design The active GPS patch antenna was chosen because of its theoretical ability to receive GPS satellite signals through the dense foliage cover in the Northern Minnesota forestry Also it will be cheaper and less time consuming to purchase an antenna rather than researching designing and building our own antenna Taoglas is a reputable GPS patch antenna manufacturer which produces both active and passive GPS antennas After communicating with a representative of the company it was determined that the Taoglas AP25b would be the best antenna for our device This antenna is only 35 millimeters square with a thickness of 4 5 millimeters It
53. but introducing the unit to the network with the assurance the unit properly utilizes the time slot is a more difficult task The unit can know precisely when to start and stop transmitting only if it knows the current time of day This can be known by using the GPS time 3 2 3 6 Initial Unit Perception of Time Consider a unit that needs to begin transmitting on the 00 10 20 30 40 and 50 mark of every hour This is hardcoded By turning on the unit and allowing it to receive a GPS signal the time of day can be obtained and a timer can be set to begin waiting for the next time to reach its time slot To be clear say the time obtained is 12 15 25 The controller would then set a timer for 00 04 35 to begin transmitting 3 2 3 7 Specific Time Slot Assignment To ensure minimal unit interruption the time slot assignment for the collar units will be staggered along the ten minute allotted time allowing for ample wait time between time slots Wireless Bear Tracking Group May1010 Page 27 For example consider a system that has eight allowed time slots for units to occupy Assume that only three units are registered to the system Units 1 2 and 3 would be assigned time slots 1 7 and 3 respectively The diagram below illustrates this 3 2 3 8 Time Slot TS1 TS2 TS3 54 55 756 757 758 Unit Assignment Figure 4 Time Slot Assignment Router Registration The routers will be required to dynamically set up an
54. char RX long check sum encode unsigned int counter unsigned int rx decode check sum unsigned char RX Wireless Bear Tracking Group May1010 Page 193 Appendix 22 PIC Code eeprom i2c c File eeprom i2c c Contains i2c funtionaility for the EEPROM include p18f46j11 h The PIC used in final design include lt i2c h gt include eeprom_i2c h define 2 Function eeprom i2c init Params void Returns void Description intialize the I2C for the EEPROM chip Rc D A x x void eeprom i2c init void TRISDbits TRISDO 1 Set pin 38 as input for I2C to function TRISDbits TRISD1 1 Set pin 39 as input for I2C to function Set MSSPEnable Bit 5 for i2c instead of SPI SSP2CON1bits SSPEN 1 1011 2 Firmware Controlled Master mode slave Idle 1000 I2C Master mode clock 5 4 SSPxADD 1 SSP2CON1bits SSPM3 1 55 2 1 1 5 55 2 SSP2CON1bits SSPM1 55 2 1 1 5 55 0 4 8 10 no clock appear until the clock was changed to 200 KHz Set I2C clock to 100 KHz ADD 0x09 SSP2ADD 0x09 return Function eeprom write byte Params byte byte to write to EEPROM address block either 1 or 0 for the page of the memory address the address of the memory Returns void Description write a byte to the EEPROM at the defined address void eeprom write byte unsigned char byte unsigned char address block Wireless
55. check3 unsigned int check 0 decodes the check sum which is located at the end of the packet The decoding requires shifting because the 5 bit encoded data was compressed 1 decode 17 gt gt 4 RX 18 lt lt 4 amp Ox1F check2 decode 18 gt gt 1 amp OxlF 4 check3 RX 18 amp OxCO check3 check3 lt lt 2 check check1 check2 check3 return check OLD FUNCTIONS NOT USED Wireless Bear Tracking Group May1010 Page 190 int check sum unsigned char packet sums all the 1 s in the entire packet then appends that to an additional byte in the packet int i20 int 3 0 int counter 0 for 0 lt 25 1 for j20 j 8 j counter packetti gt gt j amp 0x01 return counter int send message double message to send int encoded message to send encode message message to send TXSTAlbits TXEN 1 enable transmission TXREG1 encoded message to send sends encoded message return encoded message to send returns encoded message to ensure correct encoding was sent struct coordinates long latitude latitude signed long variable 4 bytes 1 7 to convert to coordinate system long longitude longitude signed long variable 4 bytes 1E 7 to convert to coordinate system unsigned long time time unsigned long variable 4 bytes ms since begi
56. clearly separated on the board Wireless Bear Tracking Group May1010 Page 133 The projects weaknesses were e The requirements could have been more quantifiable For example the team could have specified under what conditions the system could be expected to work in the number of devices the receiver should be able to handle and what level of EM radiation is safe for humans and bears Currently the system has all the components necessary to meet the specifications of the project The transceiver and GPS modules are not functioning yet and additional debugging is needed before the system will work Once those problems are identified and fixed the system should be able to meet all the requirements Wireless Bear Tracking Group May1010 Page 134 Appendix 3 and Power Amplifier Revision Schematic VHF SECTION VCOIN 1 270 742 OSci 39 8PA 1118 44 12 TP13 2 0 70 70 7070 for convinow These consact to tas irasscelver Wireless Bear Tracking Group May1010 Page 135 Appendix 4 Microcontroller Revision Schematic C SECTION 13W AWways BLE CE 3 z VHFERX LR s BHDM wil JW SHOW 139 i Rzi and are ied be anse the USART uring caly nr 1 for As fail sate JE 1 Ebe li as maing 0 cha ut i 7 Manual Reset Lor xo Hw remorse t
57. click Ports COM amp LPT This will list all ports being used on your computer From there the correct port number may be found and the Python code may be updated as appropriate Once the GPS coordinates have been read through the port in decimal form the program separates the latitude and longitude coordinates with a comma This allows the program to distinguish the coordinates Then it implants the coordinates into the basic URL structure and opens the browser to that URL 4 3 2 PIC Code This part of the document describes the files as well as the high level and low level functions written for the PIC18F46J11 microcontroller for Revision A The tools used to program this microcontroller are the following e IDE MPLAB e Programmer PICKIT2 or MPLAB ICD2 Compiler MPLAB C for PIC18 MCUs MCC18 The MPLAB project currently used is the following TDMANetwork mcp 4 3 2 1 main c This file configures and initializes the PIC18F46J11 and serves as the skeleton for the TDMA network 4 3 2 1 1 main This function calls the initialization functions and then runs the deep sleep handler function It is then decided whether the power on reset POR was pure meaning it is the first power up or was an awake from deep sleep Proper actions are then taken based on the decision 23213 activate unit This function is called when the PIC has fully wakened from deep sleep It is where communication with the GPS VHF transc
58. counter 2 The maximum value these counters can increment to is 255 or 65 025 4 3 2 3 9 power 33 This function sets the proper I O pin high or low to turn the 3 3V power supply on or off respectively 4 3 2 3 10 power 5 This function sets the proper I O pin high or low to turn the 5V power supply on or off respectively 4 3 2 3 11 vhf trx This function sets the proper I O pin high or low to turn the VHF transceiver on or off respectively 4 3 2 3 12 switch ctrl This function is called to control the RF switch to be in either receive or transmit mode This function has an unsigned character as a parameter If the argument passed through this function is 0 the switch is off If the argument passed through this function is 1 the switch is in transmit mode If the argument passed through this function 1s 2 the switch 1s in receive mode 43 23 13 swd This procedure is called when external interrupt 1 is detected which means the transceiver has found the start sequence and the data packet is going to be outputted This procedure disables external interrupt 1 SWD interrupt clears external interrupt 2 s flag and enables external interrupt 2 Data Clock By enabling external interrupt 2 the PIC is setting up to read the data outputted by the transceiver on the rising edge of the transceiver s data clock TXRXCLK Wireless Bear Tracking Group May1010 Page 90 4 3 2 3 14 VHF data rx This
59. current output requirement was again the problem the downfall of this part as well as the lack of availability b VES Figure 24 863 Wireless Bear Tracking Group May1010 Page 58 The third and chosen solution was the ADP3050 series These step down buck converters are available in 3 3V and 5 0V fixed outputs which are both used in the design Both permit very wide input rages separate shutdown pins were available and the input voltage allowed current outputs well above the requirement These devices also required very little external circuitry and are readily available unlike the previously considered Figure 25 ADP3050 3 9 3 Detailed Design The chosen design is based around an ADP3050 step down buck converter Three of these are used one for the 5V output and two for the 3 3V output 3 9 3 1 General Circuit The circuit to be used with the ADP3050 is the fixed output version The applications information suggests the following circuit This general circuit will be used in the design but the specific values shown below in Figure 26 are not necessarily the same I 22yF Figure 26 ADP3050 General Circuit Wireless Bear Tracking Group May1010 Page 59 3 9 3 2 Switching Inductor and Output Capacitor Choice for GPS Unit The GPS unit requires an input of 3 3V with a maximum ripple voltage of 50m VPP Thus the switching regulator must be designed to meet these conditions To be safe the
60. delay for 6 2 ms send gpio reg 11 send gpio reg 12 send gpio reg 0 RX for k 0 k 2 k delay for 80 us send gpio reg 4 send gpio reg 10 for k 20 k lt 340 k delay for 6 2 ms return BRR k k k k k k k k k k k k k k k k k kk k k k k k k k k k k k k k kk kk kk kk kk kk kkk kk kk kk kk kkk kkk kk kk KKK KKK OLD FUNCTIONS Not Used at the moment F Fe k ke H de He de He de He de He e KKK KK IKK KKK KKK KK de He e He k He KKK je k ke k ke k de k ke ke de k k kk k k kk kk kk k k k k k kk kk kk gt this function sets up all regesters required for eusartl transmission and reception void eusartl init void SPBRG1 207 Baud rate 207 300 baud Use SYNC 0 BRGH 0 BRG16 0 to determine SPBRG1 TXSTAlbits SYNC 0 Required for TX RX setup RCSTAlbits SPEN 1 Required for TX RX setup PIElbits TXlIE 0 No transmission interrupts PIElbits RClIE 1 Set receive interrupts INTCONbits GIEL 1 Enable global low priority interrupts INTCONbits GIEH 1 Enable global high priority interrupts RCSTAlbits CREN 1 RX setup TRISCbits TRISC7 1 Set RX pin as input TRISCbits TRISC6 0 Set TX pin as output return gt this function remaps the eusart2 pins to RP17 RX and RP18 TX for asyncrounous void eusart2VHF_remap void J EEEk e KK KKK KKK KKK kk kk kk kk kk KKK KK KKK Unlock Registers RRR RRR KKK KKK KKK k k
61. file deep sleep c author John Pritchard project Bear Tracker Project date Spring 2010 Desc This file initializes all ports needed include 18 include init h include datatypes h include handler h gt this function remaps the eusart2 pins to RP7 RX and RP8 TX void eusart2USB_remap void RRR k k ke k k KKK KKK KKK KKK k k k k k k k k k k kk kk kk Unlock Registers J EEK k k k H ke k de k de ke dk ke k ke k k k k k k k k k k k k k k kk kk kk _asm MOVLB 0 0 MOVLW 0x55 MOVWF EECON2 0 MOVLW MOVWF EECON2 0 BCF PPSCON 0 BANKED _endasm EEEk kkk kk kk kk kk kk kk kk kkk kkk Configure Input Functions See Table 9 13 EAEk kkk kk kkk kkk kk kk kk kkk kkk EEK k k k k k k k kk kk kk kk kk k k k kk kk Assign RX2 To Pin RP7 EEK k k k k k kk k k kk kk kk k k k kk kk kk _asm MOVLW 0x07 MOVWF RPINR16 BANKED endasm S EEK k k k k k kk kk kk kk k k k k k kk kk kk Configure Output Functions See Table 9 14 EEK k k k k k kk kk kk kk kk kk k kk kk kk EEEk kkk kk kkk kkk kk kk kk kkk kkk Assign 2 To Pin RP8 EEK k k k k k kk kk kk kk kk kk k kk kk kk _asm MOVLW 0x05 MOVWF RPOR8 BANKED endasm EEK k k k k ke k de k k k k k k k k k k k k k k k k k k k k k kk kk kk Lock Registers _asm MOVLW 0x55 Wireless Bear Tracking Group May101
62. i data PORTCbits RC6 reads the data pin data data lt lt VHF bit count shifts the bit to the approprate bit position byte VHF bit counttt Adds the bit to the data VHF buff VHF byte count buff VHF byte count data checks to see if the length of the packet has been captured if VHF bit count 8 amp amp VHF byte count VHF_BUFFSIZE 1 INTCON3bits INT1IF 0 clears interrupt 1 flag INTCON3bits INT21IE 0 disables int 2 VHF RX CLK INTCON3bits INT1IE 1 enables int 1 to look for sync word Signals the there is VHF data ready in VHF Buff VHF data ready 0 checks to see if the byte is complete and needs to move to the next if VHF bit count 8 VHF bit count 0 VHF byte counttt INTCON3bits INT2IF 0 clears int 2 flag return Initilizes the VHF global VHF received data and the bit and byte counters void global var init void int i VHF bit count 0 VHF byte count 0 for i 0 i lt VHF_BUFFSIZE it VHF_buff i 0x00 Wireless Bear Tracking Group May1010 Page 173 This procedures writes to the read back register of the tranciever and then reads the output of the read register signed long VHF read back long reg val int i j k b long send val reg val int data 0 data bit 0 Define bits byte bits ARRAYLEN Assigns the individual bit to the array bits for b 0 b lt 32 b bits b send_val amp 0x01
63. init void signed long VHF read back long reg val float VHF AFC RB void long VHF Silicon Rev RB void signed float VHF RSSI RB void long VHF Filter Cal RB void float VHF Battery RB void float VHF Temperture RB void extern void activate unit void extern void go to sleep void Wireless Bear Tracking Group May1010 Page 178 Appendix 17 PIC Code interrupts c Q2222 lllllllllllllllllll file tdma interrupts c author John Pritchard project Bear Tracker Project date Spring 2010 functions high vector table low vector table eusart rx int high vector low vector Desc This function handles all interrupts include 18 include interrupts h include datatypes h include handler h Define Global variables static byte eusart buff BUFFSIZE byte buff end eusart_buff BUFFSIZE byte rx eusart buff int trans error byte eusart2 buff BUFFSIZE byte buff end2 eusart2_buff BUFFSIZE byte rx2 eusart2 buff Function high vector table Params void Returns void Description Vector table for high interrupts All high interrupts come here to find out what to do next pragma interrupt high vector table void high vector table if PIR1 0x20 eusartl rx int if INTCON
64. is such a short time of exposure that the effects are very minimal Wireless Bear Tracking Group May1010 Page 113 7 Recommendation for Project Continuation This section will describe our groups suggestions for future changes to the project 7 1 VHF Recommendations In a future design the image rejection calibration in the ADF 7021 register 5 should be implemented By performing this the transceiver will be able to reject the image frequency at a higher attenuation which should decrease the bit error rate Pages 39 to 40 of the ADF 7021 datasheet explain the procedure to calibrate the image rejection A bandpass filter should be added to the output of the RF switch The band pass should allow the frequency range of 216 to 221 MHz to pass A much narrower filter design would be infeasible with the given fractional bandwidth This filter will help clean up the out of band spectrum content and help reject the image frequency By adding the filter it should help lower the bit error rate and clean up the output band content In future PCB layouts the power amplifier and transceiver ground pad should have a copper area on the solder mask along with the plated through holes to ground These copper areas will help with RF performance along with helping dissipate heat Section 4 1 1 should also be read in detail to maintain the same RF strategy and knowing to adjust the external inductor of the transceiver 7 2 Power Section Recommendations
65. k k k k k kk k k k k k k k kk kk kk _asm MOVLB 0 0 MOVLW 0x55 MOVWF EECON2 0 MOVLW MOVWF EECON2 0 BCF PPSCON 0 BANKED endasm EEK k k k k k kk kk kk kk k k k k k kk kk kk Wireless Bear Tracking Group May1010 Page 159 Configure Input Functions See Table 9 13 S EEK k k k k k kk kk kk kkk kk kk EAEk kkk kkk kkk kk kk kk kk kkk kkk Assign RX2 To Pin RP17 asm MOVLW 0x11 MOVWF RPINR16 BANKED _endasm Check ke de kk kkk kkk kk kk kk kkk kkk Configure Output Functions See Table 9 14 EAEk ke de ke kk kkk kkk kk kk kk kkk kkk EEK k k k kk kk kk kk kk kk kk k kk kk kk Assign TX2 To Pin RP18 EEK k k k k k k k k k kk kk kk kk kkk kk kk _asm MOVLW 0x05 MOVWF RPOR18 BANKED _endasm RRR RRR KKK KK KKK k k k kk k k k k k k k kk kk kk Lock Registers S EEEk kk kkk kk kk kk kk kk kk kk kk kk kk kk kkk kkk _asm MOVLW 0x55 MOVWF EECON2 0 MOVLW MOVWF EECON2 0 BSF PPSCON 0 BANKED _endasm return Wireless Bear Tracking Group May1010 Page 160 Appendix 13 PIC Code init h Define variables define VHFREGLEN 32 include datatypes h Define prototypes void void void void void void void eusart2_init byte mode eusart2USB_remap void syc eusart2VHF remap byte mode syc eusart2 init byte mode osc init void io init void vhf init byte mode extern void send gpio long re
66. procedure is called when external interrupt 2 is detected which means a rising edge was detected on the transceiver s data clock This procedure is used to read the data packet and format it in array buff The data is sent out from the PIC least significant bit first and thus as the bits are received they have to be shifted to the left to form the byte of data Once the fixed packet length is read in the procedure enables external interrupt 1 SWD and disables external interrupt 2 Data Clock 4 3 2 3 15 global var init This procedure initializes the VHF receive global variables bit count VHF byte count and VHF buff to 0 4 3 2 3 16 VHF read back This function writes to the VHF transceiver register 7 which sets up the read back function of the transceiver For more information on the specifications on read back more details can be found in Section 3 3 3 3 Register 7 s value is written to the transceiver in the same manner as the procedure send gpio Once the VHF SLE is raised high the transceiver will output data on the rising edge of the clock on line SCLK The first bit of data is to be ignored PIC reads in the data on the lower edge of the clock to ensure the data has had time to settle After the 16 bits have been read in the SLE is lowered and one more clock cycle is produced to allow the transceiver to exit readback mode 43 23 17 RB This function reads back t
67. regulator was designed such that the output ripple voltage is 25mVPP For the ADP3050 the output Vripple depends on the inductor value chosen as well as the ESR of the output capacitor The equations for this are the following Vripple ESR x L Vin Vout Iripple ripple L x Vin Vout 1 Vout x x fsw Vin 1 go fsw Vin where L is the inductor value chosen Vin is the input voltage Vout is the output voltage fsw is the switching frequency fixed at 200kHz for this device ESR is the effective series resistance Vripple is the output ripple voltage and Iripple is the output current ripple For the 3 3V step down design the input voltage is 1 5V 4 6V the output voltage is 3 3V and the switching frequency is 200kHz Using MATLAB the ESR of the output capacitor was plotted as a function of inductor choice The code and output are below in Figure 27 P Vin 6 fsw 200e3 P 1 L 0 1e 6 100e 6 Vout33 3 3 1 Iripple33 Vin 5 Vout33 L 1 fsw Vout33 Vin ili Fd ESR33 25e 3 Iripple33 plot L ESR33 Jm xlabel Inductor Value uH ylabel ESR Figure 27 3 3V ESR Calculations Wireless Bear Tracking Group May1010 Page 60 From the graph above it is shown that selecting a 22uH inductor will result in the choice of capacitor having an ESR of about 74mQ After much research it was found that
68. researchers and allow them to approach and remove collars as well as take different measurements and notes The researchers track the mother bears because they are more territorial and will stay within a twenty five mile by ten mile area The tree cover in this area is extremely dense It is important to gather live data of the location of the bears especially when the bears go into caves during winter to hibernate as well as when they leave the caves in the spring The previous solution to this tracking did not even provide live data The bears had worn collars that transmit on a VHF band Each collar outputs at a specified frequency and the researchers were required to travel and locate the bears individually by monitoring the strength of signals transmitted These collars were very reliable and transmitted well through the trees The battery life was also superb and lasted nearly five years The collars would wear through before the batteries were depleted This summer these VHF collars are being phased out by GPS personal tracking devices called SPOT These devices were modified to continually ping their data and send live location information up to a low earth orbiting satellite and then to the cabin This system fits well on the collar but in a dense forest the signal is often lost for up to two hours The SPOT units also require a monthly fee It is also very difficult to get decent battery life for the collars have batteries that must be ch
69. solder mask layer for the power amplifier s and transceiver s ground pad The revision A PCB layout has this fixed Also the crystal was bigger than the package outline However in the new design the current crystal is not being used Another consideration in changing the layout is with the inductance of L10 By changing the Wireless Bear Tracking Group May1010 Page 66 lengths of the traces from L10 to the transceiver s pins 44 46 the inductance value of L10 may need adjustment See Section 4 2 1 4 1 2 Populated Board parts were ordered and soldered onto the board as shown in Figure 30 PIC Section Antenna Connect EEPROM Power Connect GPS Patch Antenna USB Connect GPS Section Power Section USB Section Figure 30 Populated Printed Circuit Board 4 1 3 ADF 7021 Register Configuration The ADF 7021 uses registers to configure it in either transmit or receive mode There is a sequence to follow to configure the transceiver in transmit or receive mode which can be seen in Figure 9 and Figure 10 It should be noted that a lot of these values are based on the current hardware Revision A If the crystal oscillator is changed to a voltage controlled oscillator with a better frequency accuracy as suggested the register values will change 4 1 3 1 Transmit Mode The following steps show the order for configuring the transceiver in transmit mode 1 Set VHF CE High Setting the CE high turns on
70. solution currently being used by the researchers and incurred the same sort of cost that they are looking to eliminate Next we were able to rule out the Digi OXtend solution after doing field tests that resulted in an unacceptable 2 mile range from line of sight This transmission would be drastically reduced in the wooded areas of Minnesota The VHF Routing Unit solution allowed for these constraints to be overcome Not only is it a low cost solution but it also gives us the ability to choose a frequency that works best for our conditions With the selected frequency of 217 we are able to penetrate very dense forestry while still maintaining a reasonable range This was verified using the Radio Mobile simulation software 4 2 End User 4 Wireless Bear Tracking Group May1010 Page 21 3 2 Network Structure The following section will define the network routing schemes proposed and why TDMA was chosen as the preferred networking method The detailed design of the network method is also described The sole purpose of this section is to propose a versatile solution to the unit to router communication scheme as well as the router to router communication scheme 3 2 1 CSMA CA CSMA CA is a networking solution that stands for Carrier Sense Multiple Access with Collision Avoidance A user will listen to the channel for a period of time before transmitting If the channel is clear the user
71. start sequence 4 2 3 Transceiver External Crystal The current crystal that was picked out has a frequency tolerance of 30ppm The recommended tolerance rate for narrow band applications which is given on page 22 of the transceiver data sheet is to have a lt 10ppm Digikey does not stock crystasl with these specs However there are voltage controlled oscillators VCXO that have this specification A possible replacement is Digikey part number 631 1068 1 ND This VCXO has a frequency tolerance of 1 5 ppm at frequency of 12 MHz which will still allow us to have exactly a 300 baud rate It should be noted that if this VCXO is used Wireless Bear Tracking Group May1010 Page 83 instead of the current crystal the values in the registers will have to be changed based on this new frequency of 12 MHz 4 2 4 2 The I2C lines were used by the PIC to operate an EEPROM memory chip and a UBLOX NEO 5Q module Both units operated on different SCL and SDA lines so that each unit could be debugged separately The I2C modules are available on the PIC and code was supplied by Microchip However each unit required debugging especially the UBLOX module In I2C the unit has to address the slave on the line and then wait for the slave to respond with valuable information The EEPROM would respond with the data stored in its memory The UBLOX GPS chip would respond with NMEA and proprietary UBX data messages The UBLOX Protocol Specifications docume
72. the home computer is already known the routers can each calculate which router is the closest router to the path back to the home computer The router will know that it must then transmit to this router By only sending it to the closest router to the path back to the home computer it will save time and allow for fewer transmissions therefore saving battery power The receiving router will store the data until it is its turn to transmit the data This process will continue for a length of time that is dependent on the number of routers Each router will not have its own time slot because the amount of data that each router needs to send is dependent on the number of bears in range of the router as well as the amount of data that was forwarded to the router by the previous routers 3 2 3 9 Bear to Router Communication With this solution when a bear collar transmits its location multiple routers could receive the location Each router will know the location of the other routers so the closest router will send the acknowledgement to the bear One exception to this would be if the closest router did not receive the bear s transmission Since the bear will not receive the acknowledgement according to the conditions laid out above the bear will retransmit the signal When the router receives the bear s transmission for a second time the second closest router will then try to send the acknowledgement This condition is in place because if two route
73. the required presentations for the Senior Design course and to demonstrate the end product to the client 8 6 1 Subtask 6 1 Project Plan The objective of Subtask 6 1 is to create a power point presentation of our project plan and present this presentation to the Senior Design class The presentation will cover the main aspects of our project plan document 8 6 2 Subtask 6 2 Design Review The objective of Subtask 6 2 is to create a power point presentation of our design and present this presentation to the Senior Design class and review committee The presentation will cover the main aspects of our design from Task 3 8 6 3 Subtask 6 3 Client The objective of Subtask 6 3 is to demonstrate the end product to the client We will demonstrate the capabilities of the end product and the fulfillment of requirements 8 6 4 Subtask 6 4 Industry Review Panel The objective of Subtask 6 4 is to create a power point presentation of the main aspects of our final end product and present the presentation to the industry review panel 8 7 Task 7 Product Documentation The objective of Task 7 is to create necessary documentation to plan the project and record the initial and final designs of our end product 8 7 1 Subtask 7 1 Project Plan Development The objective of subtask 7 1 is to create a document that captures the requirements and plans necessary to create the end product The document will guide our decisions in the developm
74. to PIC I O Descriptions VHF TX Serial data that is sent to be transmitted VHF RX VHF received data from another device VHF SCLK Serial clock input for writing and reading to the registers of the transceiver VHF WRITE Serial data input data to be loaded into the registers of the transceiver VHF READ Serial data output register data of the transceiver VHF SLE Load enable input set high to load data into register VHF CE Chip enable low puts transceiver in power down and register values are lost VHF SWD Sync word detect high when a match for the sync word sequence found VHF MUXOUT Digital pin that can be set to read various set conditions Default is Regulator Ready pin is set high when the regulator is ready on power up ANT CTLO Antenna Control bit 0 of the antenna switch Set 0 for TX and 1 for RX ANT Antenna Control bit 1 of the antenna switch Set 1 for TX and 0 for Wireless Bear Tracking Group May1010 Page 33 To write to the transceiver s register the data is read in on the rising edge of the SCLK The registers are 32 bits in length and are fed in most significant bit to least significant bit During this time SLE must be held low After the last bit rising clock has been read in VHF SLE must be raised high for at least 20 ns to move the data into the registers Table 2 and Figure 7 below from the ADF7021 datasheet show the timing requirements
75. to make sure the message is a NAV POSLLH message class msg class gpsdata id ubx msg id gpsdata if class 0x01 amp amp id 0x02 Checks the longitude of the message to make sure it is and thus valid for the United States also make sure the accuracy of the message is acceptable longitude ubx navpllh get longitude gpsdata accuracy msg ubx navpllh get accuracy gpsdata if longitude 1 amp amp accuracy msg accuracy Wireless Bear Tracking Group May1010 Page 205 valid 1 Only allows to increment to 250 which is about 2 to 3 minutes time outtt return valid Wireless Bear Tracking Group May1010 Page 206 Appendix 25 PIC Code gps i2c h ifndef GPS 2 H define GPS I2CH Function gps i2c init Params void Returns void Description intialize the I2C for the EEPROM chip Function gps read Params rdptr Character type pointer to PICmicro MCU RAM for storage of data read from I2C device length Number of bytes to read from I2C device Returns none Description reads all buffered information from the GPS Function gps write Params dataptr Character type pointer to data to write length Number of bytes to write to I2C device Returns void Description write a CFG message to the UBLOX void gps write unsigned char message unsigned char length Function gps read loop Params void Returns void Description pol
76. to the GPS only for the purposes of configuration Therefore this message will often not be used by itself but by another configuration function 4 3 2 7 4 gps read loop At times the UBLOX may not respond to an address but this function will loop and end with a read request after the UBLOX acknowledges This function is not often used outside of the gps read function 4 3 2 7 5 gps write loop At times the UBLOX may not respond to an address but this function will loop and end with a write request after the UBLOX acknowledges This function is not often used outside of the gps write function Wireless Bear Tracking Group May1010 Page 97 4 3 2 8 Ublox cfg c This file contains all of the configuration messages used to set up the UBLOX NEO 5 for the bear application The functions package a correct configuration message and then write it to the GPS 4 3 2 8 1 ubx cfg port poll A request is made for the UBLOX to output its current port configuration on the output Data Stream to be read by the PIC 4 3 2 8 2 ubx cfg port This sends a configuration message to the UBLOX The only important setting is that this message changes the protocol from NMEA to UBX protocol 4 3 2 8 3 ubx cfg msg off Different message types are outputted automatically to the data stream as a boot time configuration of the UBLOX NEO 5 This function turns off a message of the above class and id as inputs 4 3 2 8 4 ubx cfg msg on
77. trx cfg This function is called if the Configure Transceiver choice is selected Once implemented this function will run through the procedure needed to properly configure the transceiver for transmission or reception mode 4 3 2 5 8 send data This function is called if the Send Data via Transceiver choice is selected Once implemented this function will send data to the transceiver that is then sent by RF 4 3 2 5 9 gps test This function is called if the GPS Testing Program choice is selected This function outputs a static GPS coordinate an infinite amount of times This is used when using the Google Map interface 4 3 2 5 10 choice disp1 This function is called by user ctrl to display the first set of choices once a user types in the HyperTerminal 4 3 2 5 11 choice disp2 This function is called by user ctrl to display the second set of choices once user types in the HyperTerminal 4 3 2 5 12 choice disp3 This function is called by user ctrl to display the third set of choices once a user types in the HyperTerminal 4 3 2 5 13 reset buff2 This function resets the user input buffer 4 3 2 5 14 This function takes a string and prints it to the HyperTerminal It sends data byte by byte using the EUSART2 module It then sends two more bytes a return carriage and a new line indicator Wireless Bear Tracking Gr
78. used in the wireless communication and how the information will go from the bear to the end user We will research different methods and pick the appropriate method 8 2 7 Subtask 2 7 Security The objective of Subtask 2 7 is to select the necessary security of the wireless communication to prevent unauthorized access to the transmitted data We will approach this task by determining the appropriate amount of security and the method to protect the data Wireless Bear Tracking Group May1010 Page 118 8 3 Task 3 End Product Design The objective of Task 3 is to develop the design of the end product The design will be of the unit on the bear and any necessary routers The design includes both hardware and software We will approach this task by dividing the necessary work between the members of the team based on expertise and desire to work on a specific task 8 3 1 Subtask 3 1 Electrical Hardware The objective of Subtask 3 1 is to design the electrical hardware of the unit on the bear and any necessary routers In this task we will create block diagrams and schematics to show the electrical layout of all the parts We will run any necessary simulations to test our designs We will also create the printed circuit board layout which will be used to fabricate the printed circuit board We will acquire sample parts in order for us to test initial part performance to make sure the part is applicable to our project 8 3 2 Subtask 3 2
79. will need to be shielded from this antenna portion Wireless Bear Tracking Group May1010 Page 43 The antenna extended along inside the collar will be made from stranded steel aircraft cable This is a similar material to other wildlife telemetry antennas There are several different types of aircraft cable but the most important quality is thickness The stranded cable allows for it to be flexible as it wraps around the neck The diameter of the cable must be wide enough to account for the bandwidth of the signal As the cable of the antenna widens the higher bandwidth capability of the antenna will increase Figure 16 Example Whip Collar Antenna Advanced Telemetry Systems e Antenna is easily made e Very inexpensive e Very flexible around the neck of the bear Does not protrude out of the collar Can match the impedance with discrete components e Antenna is not shielded properly and will also accept a lot of noise e The curvature of the antenna will not allow for the ground plane to be perpendicular to the antenna and possibly allow interesting results e Research has shown that the ground plane should be several wavelengths long to produce a stable impedance input Wireless Bear Tracking Group May1010 Page 44 3 4 2 Wavelength Whip Antenna This antenna is very similar to the 4 wavelength except it will have a much longer physical length This increase in length will also allow a higher antenna gain
80. will notify all other users not to transmit and then proceed to transmit the information packet 3 2 2 TDMA TDMA will be described in depth in the detailed design section but its basic concept is that several users will transmit on the same frequency but for different time slots The individual user is allocated a time to transmit and during that time period the channel is clear After the time has passed the channel is clear for a second user to transmit There were several reasons considered when choosing TDMA over CSMA CA CSMA CA is useful when users activities are bursty and also when the number of users of the system varies dynamically CSMA CA allows simple adaptation to these conditions However since in the current application the system is quasi static and the number of users does not change except in rare situations in addition to the fact those users activities are deterministic 1 report every 10 minutes TDMA is better suited for the application Moreover with TDMA the hidden terminal problem can be avoided the exposed terminal problem can be avoided and the ad hoc network topology can be supported in a simple way This strategy will also save energy since it will avoid the collisions that CSMA CA suffers from The use of a GPS chip also makes synchronization a simple task 3 2 3 Detailed Design This section gives an introduction to the overall network skeleton as well as the network protocol chosen Wireles
81. xml urllib urlopen url read if lt error gt in xml print nGoogle cannot interpret the address else f Strip lat long coordinates from XML lat lng 0 0 0 0 center xml xml find center 13 xml find xml find center center center replace lat replace lng lat lng center split url http maps google com maps q s 4 s lat lng i print 5 url s os startfile url ser flush ser flushInput ser close Wireless Bear Tracking Group May1010 Page 145 Appendix 10 PIC Code main c 2 file deep sleep c author John Pritchard project Bear Tracker Project date Spring 2010 Desc This file configures and initializes the PIC18F26J11 Its purpose right now is to serve as a template for the TDMA networking scheme This program initializes the PIC sets a time interval then sleeps for that interval The PIC then wakes flashes a set of LEDs then goes back to sleep include main h include datatypes h include interrupts h include init h include handler h include user h include encoding h include ublox read h include gps i2c h include eeprom i2c h include lt string h gt Set configuration bits see datasheet for details if defined __
82. 0 Configures the PIC for transciver RX mode eusart2VHF remap eusart2 init RX Turns on the 3 3 line and makes sure the 5V line is OFF power 33 power 5 OFF turns on the transceiver switches the RF switch to RX mode vhf trx ON Switch ctrl RX Delay to allow the transciever to power up for k 0 k lt 90 k delay for 3 6 ms Configures the receiver to RX mode vhf init RX Waits until the VHF data is ready while VHF data ready if i 100 0 Avg Avg RB 2 itt for k 0 k lt 3000 k Decodes the packets check sum and recalculates the check sum decode chk sum rx decode check sum VHF rx calc chk sum check sum VHF rx 17 Checks for bit errors if decode chk sum calc chk sum success 1 decodes the message and assigns to the corrisponding global variables lat rx decode lat VHF rx lon rx decode lon VHF rx time rx decode time VHF rx status rx decode status VHF rx ID rx decode ID VHF rx Wireless Bear Tracking Group May1010 Page 170 Resets the VHF Buff and the RX counters and the flag when VHF data is ready global var init VHF data ready 1 powers down the transciever vhf trx OFF power 33 OFF return success Returns the current latitude from the RX data signed long get lat void return lat Returns the current longitude f
83. 0 gt gt 5 RX 11 lt lt 3 amp 0x1F lt lt 4 lat3 decode message RX 11 gt gt 2 amp OxlF 8 Wireless Bear Tracking Group May1010 Page 189 lat4 decode message RX 11 gt gt 7 RX 12 lt lt 1 amp 0x1F 12 lat5 decode message RX 12 gt gt 4 RX 13 lt lt 4 amp 0x1F 16 lat6 decode message RX 13 gt gt 1 amp 0x1F 20 lat7 decode message RX 13 gt gt 6 RX 14 lt lt 2 amp 0x1F 24 lat8 decode message RX 14 223 amp 0x1F 28 lat latl lat2 lat3 lat4 lat5 lat6 lat7 lat8 return lat Decodes the status data from the encoded shifted packet unsigned char rx decode status unsigned char RX statusl status2 status 0 statusl status2 decode message RX 15 amp Ox1F decode message RX 15 gt gt 5 RX 16 lt lt 3 amp OxlF 4 status statusl status2 return status Decodes the ID data from the encoded shifted packet unsigned char rx decode ID unsigned char RxX char ID1 ID2 ID 0 1 1 ID2 decode message RX 16 gt gt 2 amp Ox1F decode message RX 16 gt gt 7 RX 17 lt lt 1 OxlF 4 ID ID1 ID2 return ID Takes in the recieved packet and decodes the check sum of the packet unsigned int rx decode check sum unsigned char RX unsigned int checkl check2
84. 0 MHz This band allowed a high power transmission However at a frequency of 40 MHz our antenna for the VHF would require an antenna length of 6 2 ft which is too long for the units on the bears Federal Communications Commission Part 18 The final band we consider was the licensed band at 216 to 220 MHz The band allows a maximum output power of 2 watts and bandwidths of 6 25 12 5 25 and 50 kHz The band is assigned to applicants that establish eligibility in the Industrial Business Pool The Industrial Business Pool includes uses in the operation of educational institutions which our final product would qualify for The downside to this band is that it would require certification from the FCC Federal Communications Commission Part 90 In the end we chose the license band at 216 to 220 MHz More specifically the exact frequency the units will operate at is 217 025 MHz The band is in the VHF spectrum and will allow us to transmit at power levels that are needed With the requirement of needing a license our client informed us that we do not need to certify our product and any certification needed would be done by them 3 3 2 Transceiver Selection Due to time constraints of the project and the availability of VHF transceiver modules our team decided to consider only VHF transceiver modules instead of trying to build our own transceiver We considered three different modules Radiometrix UHXI Melexis TH7122 and Analog Devices ADF7021
85. 0 Page 153 Maps the programmable pins to be set up for Syncrounous TX RX MOVWF EECON2 0 MOVLW MOVWF EECON2 0 BSF PPSCON 0 BANKED endasm return void syc eusart2VHF remap byte mode k k kk kk kk Unlock Registers de ke dk ke k k k k k k k k k k k k k k k k kk kk kk _asm MOVLB 0 0 MOVLW 0x55 MOVWF EECON2 0 MOVLW MOVWF EECON2 0 BCF PPSCON 0 BANKED endasm EEEk kkk kk kk kk kk kk kk kk kkk kkk Configure I O Functions See Table 9 13 EEK k k k k k k k kk kk kk kk kk k kk kk kk if mode 1 TX Mode Assigns Pin 44 as the TX data line for USART 2 Assigns Pin 1 RP18 as input clock for USART 2 asm MOVLW 0x06 MOVWF RPOR17 BANKED MOVLW 0x12 MOVWF RPINR17 BANKED _endasm else RX Mode Assigns External Interrupt 1 to Pin 4 RP23 for SWD Assigns External Interrupt 2 to Pin 1 RP18 for CLK _asm MOVLW 0x17 MOVWF RPINR1 BANKED MOVLW 0x12 MOVWF RPINR2 BANKED endasm J EEK k k ke k de H de He de ke dk ke k ke k k k k k k k k k k k k k k kk kk kk Lock Registers J Choke ke e ke kkk kkk kk kk kk kk kk kk kk kk kk kkk kkk _asm MOVLW 0x55 MOVWF EECON2 0 Wireless Bear Tracking Group May1010 Page 154 MOVLW MOVWF EECON2 0 BSF PPSCON 0 BANKED endasm return gt this function sets up all regesters required for eusart2 transmission and lt
86. 0010 00 0011 AGC CLK SEQ CLK CDR Clk DEM CLK BBOS Clk Address Divide 10 Divide 40 Divide 210 Divide 2 Divide 4 Table 8 TX Register 3 value Wireless Bear Tracking Group May1010 Page 68 Baseband offset clock frequency BBOS CLK must be greater than 1 MHz and less than 2 MHz where BBOS CLK is given by the following equation where BBOS CLK Divide equal to 4 gave us the desired frequency XTAL Frequency _ 4 032MHz 008MHz BBOS CLK Divide The demodulation clock needed to be set between 2 MHz and 15 MHz The demodulation clock is given by the following equation where a value of 2 gave us the desired frequency XTAL Frequency 4 032MHz Es 2 016MHz DEMOD _ Divide 2 For 2FSK the data clock recovery frequency CDR CLK needs to be within 296 of 32 times the data rate In our case the data rate was 300 bits sec given a CDR CLK of 9 6 kHz The CDR CLK is given by the following equation where CDR DIVIDE needs to be a value of 210 DEMOD CLK _2 016MHz CDR _ CLK _ Divide 210 9 6kHz Sequencer clock SEQ CLK supplies the clock to the digital receiver block and should be close to 100 kHz as possible The SEQ CLK is given by the following equation with a value of SEQ DIVIDE being 40 giving us the closest value to 100 XTAL 4 032MHz 100 8kHz SEQ _ CLK _ Divide 40 Wireless Bear Tracking Group May1010 Page 69 step to sett
87. 100k 1M 10M Frequency Hz Power On Transient Frequency MHz 50 60 Time us Freq Error Abs Frequency Error Hz Time us Figure 15 ADF7021 Simulations Wireless Bear Tracking Group May1010 Page 41 3 3 3 10 External Power Amplifier The output from the ADF7021 is fed into an external power amplifier made by RFMD SPA 1118 This external power amplifier amplifies the power by 17 2 dB and has a 1 dB compression of 29 5 dB The matching network and bias network was supplied by RFMD The values of the external components were optimized for a frequency of 240 MHz and are matched to 50 ohms The application engineer from RFMD suggested starting with the values and then slightly adjusting them once the board is built to achieve an optimal match 3 3 3 11 RFSwitch A RF switch connects the output RF of the external power amplifier and the RF input of the transceiver to the common antenna The RF switch is made my Skyworks SKY13270 92LF The switch has a 0 1 db compression point of 37 dBm and can handle up to 6 watts of power The switch isolates the high power transmission from the RF input of the transceiver The isolation helps prevent any damaging to the RF input of the transceiver ANT CTLO and are the control lines from the microcontroller shows the control lines settings for transmitting and receiving Table 3 RF Switch Control Lines ANT CTLO ANT CTLI Transmit 1 0
88. 1110 0b1111 050000 return decoded message The procedure takes in the latitude longitude time status and ID and formats it into 4b 5b Once in 4b 5b the procedure compresses the data to reduce the number of bytes send The compression takes into advantage of the fact that each encoded 4b 5b message has three empty bits Thus data in the next byte can be shifted into these three empty bits void format packet unsigned char packet signed long latitude signed long longitude unsigned long time unsigned char status unsigned char ID int i char message array 32 unsigned char message message array int counter 0 splits up the latitude longitude and time in 4b 5b encoding into 8 bits and encodes them into 4b 5b for 1 0 1 lt OCT 4 i messageti encode message latitude i 4 amp 0x0000000F messagetit8 encode message longitude i 4 amp 0x0000000F messagetit16 encode message time i 4 amp 0x0000000F encodes the status and ID into 4b 5b 24 encode message status amp Ox0F 25 encode message status gt gt 4 amp Ox0F 26 encode message ID amp OxOF message t27 encode message ID gt gt 4 Ox0F Compresses the encoded data since each byte in message only contains 5 bits The compressions moves bits from the next message into the prevouis b
89. 18F26J11 defined 18F46J11 pragma config WDTEN OFF XINST OFF OSC INTOSC pragma config T1DIG ON LPT10SC OFF DSWDTOSC INTOSCREF pragma config RTCOSC INTOSCREF DSBOREN ON DSWDTEN ON pragma config DSWDTPS DSPER FCMEN OFF IESO OFF define ON 1 define OFF 0 define TX 1 define RX 2 define VHF 0 define USB 1 used for testing purposes to determine the transmission error rate int error 0 trans 0 Wireless Bear Tracking Group May1010 Page 146 Main lt function main desc This is the main function that initializes registers required for the to function properly It also is where the deep sleep wakeup is checked If is just powering up for the first time then it did not wake from a deep sleep and will perform normal Power On Reset POR actions If the PIC wakes from being in deep sleep logic is set in place to determine the proper course of action void main void int activate chk 0 Do some initialization maintenance first osc_init do this first io init do this before any com port inits activate chk ds handler Run DS handler to see if normal POR or deep sleep POR activate unit if activate chk 1 If it is a pure POR do this Write DS
90. 3bits INT1F 1 swd Wireless Bear Tracking Group May1010 Page 179 if INTCON3bits INT2F 1 VHF data rx if PIR3 amp 0 20 eusart2 rx int else Nop Function low_vector_table Params void Returns void Description Vector table for low interrupts All low interrupts come here to find out what to do next pragma interrupt low_vector table void low_vector table Nop Do nothing No low priority interrupts have been set up at this time Function interrupt_euart Params void Returns void Description Interrupt point when rx data is received Loads rx data into a buffer and checks for any ids that were received void eusart2 rx int void TXSTAlbits TXEN 0 clear TX enable this clears TX int flag TXSTA2bits TXEN 0 rx2 RCREG2 2 if rx2 gt buff end2 rx2 eusart2 buff return Function high vector Params void Returns void Description interrupt point for high interrupts pragma code high vector section 0x08 Wireless Bear Tracking Group May1010 Page 180 void high vector void _asm GOTO high vector table _endasm Function low vector Params void Returns void Description interrupt point for low interrupts pragma code low vector section 0x18 void low vector void asm low vector table _endasm gt e e e He he e He he KKK KK e He he e He
91. 4 5 20 m ao 5 E 25 5 30 d 35 7 40 100 150 200 250 300 350 400 450 500 100 140 200 240 30 340 400 440 500 freq MHz freq MHz Figure 32 Transceiver output matching network simulation with non ideals E ubst MSu NUD Ls fncude f i ue W nmj MEETS 000 MURATA cude S bst MS b1 Modellnclude Panasonic muRata W 30 0 mil Panasonic Models 3 SENE L 80 0 mil LQG18 L8 Value 47 Value 100 nHf ME b 0603 ECJZ Cl ss2 caia W 32 0 mil peat d M W 120 mil 215760 mil EEE TL Subst MSubt paren Subst MSubt o pais C0603 ECJZ Class value 1000pF EE dep W 120 mil NS DCN DEI LEE VEZU ml L 2210 mil a d SEE L 206 0 mil gt partName ECJZECTETRSC 5 1 valuez1 5pF 3 MLIN TES MSUB gt gt RFIN PIN6 Subst MSubl MSub1 pm s 109 mil H 62 mil Eu RFINB PIN7 1 1310 0 mil Er48 R 1 R5 j C nd 5 BE47 438 kOhm am 3 98 034 mil K R Term2 T21 4 mil 6 cc DATE dis 0 C 2 40 pF R 374 Ohm R 374 Ohm 2 50 Ohm Rough mil T Figure 33 Transceiver input matching network circuit with non ideals Wireless Bear Tracking Group May1010 Page 81 m5 freqz217 0MHz dB S 2 2 22 482 45 dB S 2 2
92. 50 Factor 2081 Enable On 15 16 Table 23 RX Register 10 value AFC is used to remove frequency errors due to mismatches between the transmit and receive crystals The AFC Scaling Factor is given by the following equation 2 x500 AFC_SCALING _ FACTOR Round XTAL Analog Devices In our case the XTAL is 4 032 MHz which results in a AFC_Scaling_Factor equal to 2081 KI equal 11 1011 and KP equal to 4 100 are the recommended settings to give optimal AFC performance The MAX AFC correction range should be less than or equal to 1 5 IF filter Bandwidth From Register 4 our IF filter BW is equal to 25 kHz resulting in a MAX AFC Correction of less than or equal to 37 5 kHz The MAX_AFC_RANGE is given by the following equation AFC Correction Range MAX_AFC_RANGE x 500 Hz Analog Devices Setting the AFC correction range at 25 kHz gives us a MAX_AFC_RANGE of 50 RX Mode Set VHF_CE low to power down Wireless Bear Tracking Group May1010 Page 79 4 1 4 Matching Networks With the PCB design completed we re simulated our matching networks for the transceiver with non ideal parts and traces using Advanced Design System 2009 We used models for the inductors and capacitors from Murata and Panasonic and PCB board characteristics given in Table 6 From these simulations we only needed to increase L8 inductance to maintain our 50 ohm matches Figure 31 Figure 32 Figure 33 and Figur
93. B1 bits 28 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 27 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 26 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 25 for j 0 j lt 2 34 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 24 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 23 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 22 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 21 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 20 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 19 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 18 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 17 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 16 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBb
94. BX NAV PLLH message Returns Signed Long of longitude Description Returns longitude of the message lowest seven digits are decimal Returns in 1 7 signed long ubx navpllh get longitude unsigned char message signed long longitude longitude 0x0000FF amp message 13 longitude longitude 8 longitude longitude 0 0000 amp message 12 longitude longitude 8 longitude longitude 0 0000 amp message 11 longitude longitude 8 longitude longitude 0x0000FF amp message 10 return longitude Function ubx navpllh get msTOW Params message Character type array UBX NAV PLLH message Returns unsigned Long of ms time of week Description Returns the unsigned long of ms so far in the week unsigned long ubx navpllh get msTOW unsigned char message unsigned long msTOW msTOW 0x0000FF message 9 msTOW msTOW lt lt 8 msTOW msTOW 0 0000 amp message 8 msTOW msTOW lt lt 8 msTOW msTOW 0 0000 amp message 7 msTOW msTOW lt lt 8 msTOW msTOW 0 0000 amp message 6 return msTOW Function ubx navpllh get accuracy Params message Character type array UBX NAV PLLH message Returns unsigned Long accuracy measurement in mm Description Returns the unsigned long of estimated accuracy measurement in milimeters Wireless Bear Tracking Group May1010 Page 216 unsigned long ubx navpllh ge
95. Disables ADC Noltage of the battery Battery Voltage Readback 21 1 return data 21 1 Reads back the Temperature which is degrees Celecius float VHF Temperture RB void long reg val 0 167 long data 0 send 0 1708 enables ADC data VHF read back reg val data data amp Ox7F masks the data so only first seven bits are used send_gpio 0x16D8 Disables ADC return 40 68 4 data 9 32 Wireless Bear Tracking Group May1010 Page 177 Appendix 16 PIC Code handler h define SCALAR1 100 SCALAR1 255 SCALAR2 postscalar time Sleep period in milisec approx define SCALAR2 0 SEE TDMA MAIN H FOR POSTSCALAR VALUE DSPER needs to stay in tdma main h define ARRAYLEN 32 define VHF BUFFSIZE 19 include datatypes h Define prototypes void send eusartl int datatx int dpslp chk void void sleep count void void eusart test void int ds handler void void wake to sleep void void power 33 byte x void power 5 byte x void send gpio long reg val void vhf trx byte x void switch ctrl byte x void send eusart2 int datatx unsigned char VHF RX Mode void signed long get lat void signed long get lon void unsigned long get time void unsigned char get status void unsigned char get ID void void VHF TX Mode void void VHF send packet unsigned char packet void swd void void VHF data rx void void global var
96. GPR 0x00 0x00 write zeros to the registers that retain values in deep sleep We will store counter data here maintenance perform first startup maintenance go to sleep call the go to sleep function in the handler file if activate chk 2 Tf it is a deep sleep increment wake multiple of a DSWDT postscalar do this go to sleep if activate chk 3 Tf it is a deep sleep final wake final multiple of a DSWDT postscalar do this activate unit else Nop while 1 return Wireless Bear Tracking Group May1010 Page 147 FF FEN function activate_unit desc This function serves to manage the unit s activities once it is fully awake This means that in this function the unit will receive GPS data manipulate it and send it to the transceiver Future activities will need to be implemented 0X 0X void activate unit void if KEEP THESE NEXT TWO LINES Write zeros to the registers that retain values in deep sleep We will store counter data here Write DSGPR 0x00 0x00 go to sleep return Used for Demo makes the unit a transmitter only void TX unit unsigned int gps i2c init initializes the GPS while 1 Get GPS data and send it VHF TX Mode Delay to allow time for the power amplifier to cool down for k 0 30000 k delay for k 0 30000 k delay void
97. MHz unit and be mounted above the tree line Pros VHF can transmit at increased distances using lower power rates VHF frequencies easily penetrate heavily wooded areas The 9Xtend module is manufactured by Digi The 9Xtend module will make the network structure very easy to implement Cons Readily made VHF module is not easily accessible with high power output Bears may travel outside range of stationary routers The transmission of the 9Xtend was only tested to reach approximately 2 5 miles with line of sight 3 1 4 Other Inappropriate Solutions The following solutions were looked into for a short period to evaluate their feasibility but were quickly removed from consideration for the given reasons Cellular Tower coverage is extremely weak in area Subscription cost is expensive Difficult to certify device Signal is too high frequency Wireless Bear Tracking Group May1010 Page 20 IRIDIUM Satellite Communication No readily available module Too high frequency for good signal reception Satellite Modem on Collar Both IRIDIUM and OrbCom constellations Too high of power for collared unit Modules too large for collared unit DigiMesh 900MHz Collar Mounted Solution Signal power too low to give adequate transmission range 3 1 5 Detailed Design The chosen solution was VHF Collar Units with VHF Routing Unit After evaluating the Orbcom solution we realized that this was too similar to the
98. Matching Network Simulation eere 40 Eigure I5 ADF7021 Simulati Qs aio o a io icon pecias tuas Uber vias las EO 41 Figure 16 Example Whip Collar Antenna Advanced Telemetry Systems 44 Figure 17 Sleeve Dipole Antenna Saunders and 7 2 46 Figure 18 Helical Antenna BUPDOFEy ueniet trita b ich ete cue ager da 48 Figure 19 Six Element Yagi Antenna Setian tran 49 Figure 20 Radio Mobile Area of Concern oae dte Exerc capture era teo 51 Figure 21 Radio Mobile Router Station 52 gcn 22 EMS I m DC err 57 Fig r 23 2717 58 gua T 58 Fig te 25 ADP3050 NT 59 Figure 26 ADP3050 General iplb epo iB acta 59 Fig re 27 3 3V ESR Calculations 60 5 5 V ESR Calculations E 62 29 PCB viver MT 65 Figure 30 Populated Printed Circuit BOSE oii iatis itte peu Eire msan Eb regias 67
99. Number of bytes to write to I2C device Returns void Description write a byte to the EEPROM at the defined address eprom write unsigned char address block unsigned int address unsigned char dataptr unsigned char length unsigned char eeprom control high address low address k byte IdleI2C2 ensure module is idle StartI2C2 initiate START condition while SSP2CON2bits SEN wait until start condition is over load EEPROM control byte in buffer 1 4 1010 3 address block shown as input to function lt 2 1 gt hardware defined address 00 in this case 0 0 for write eeprom control 0 address block amp 0x01 lt lt 3 0x08 WriteI2C2 eeprom control write 1 byte R W bit should be 0 IdleI2C2 ensure module is idle load high byte of address into buffer high address address gt gt 8 amp Ox00FF WriteI2C2 high address write address byte to EEPROM Wireless Bear Tracking Group May1010 Page 197 IdleI2C2 ensure module is idle load low byte of address into buffer low address address amp 0 00 WriteI2C2 low address write address byte to EEPROM IdleI2C2 ensure module is idle for k 0 lt length byte dataptr WriteI2C2 byte Write data byte to EEPROM IdleI2C2 ensure module is idle StopI2C2 send STOP condition while SS
100. P2CON2bits PEN wait until stop condition is over eeprom ack polling Wait for write cycle to complete return return Wireless Bear Tracking Group May1010 Page 198 Appendix 23 PIC Code eeprom i2c h ifndef EEPROM I2C H define EEPROM I2C H Function eeprom i2c init Params void Returns void Description intialize the I2C for the EEPROM chip Function eeprom write byte Params byte byte to write to EEPROM address block either 1 or 0 for the page of the memory address the address of the memory Returns void Description write a byte to the EEPROM at the defined address TEM C P a ee RR RPM PR ee A ON void eeprom write byte unsigned char byte unsigned char address block unsigned int address Function eeprom read Params address block either 1 or 0 for the page of the memory address the address of the memory rdptr Character type pointer to PICmicro MCU RAM for storage of data read from I2C device length Number of bytes to read from I2C device Returns none Description read from the EEPROM void eeprom read unsigned char address block unsigned int address unsigned char rdptr unsigned char length Function eeprom ack polling Params void Returns void Description poll the EEPROM chip to see if it is busy for a page write void eeprom
101. Page 84 Figure 36 Quarter Wave Antenna Construction 4 3 Software The following section describes the functionality and scope of the software portion of the 4 3 1 PC Code This portion describes the mapping of GPS coordinates onto Google Maps 4 3 1 1 Google Mappping Code Google Maps is a handy and user friendly tool that we thought would give the researchers a better way to locate the bears and have a better visualization of that location So using the scripting language Python we wrote a code that will extract the GPS data sent by the PIC and automatically launch a browser and plot those coordinates on Google Maps This code can be seen in Appendix 6 Initially the set up of the port is needed Since we are using serial communication we were able to implement the pySerial API This makes it very easy to access the ports needed and also allows us to set the various parameters ser serial Serial port 6 baudrate 2400 bytesize EIGHTBITS parity PARITY NONE stopbits STOPBITS ONE timeout None xonxoff 0 rtscts 0 interCharTimeout None The only thing that needs to be monitored is the port number Since a computer may already be using port 6 it may require some modifications to read from the correct Wireless Bear Tracking Group May1010 Page 85 port that the board is connected to via USB In order to view the port being used after plugging in the device open the Device Manager application and double
102. Serial data activity is exhibited in times of serial communication serial ports will be observed using an oscilloscope Controller status will be checked in times of low power mode to get an accurate low power consumption rate 5 5 Chassis Unit Level Test Cases In order to test the durability and resistivity of the cases to the environments a variety of tests can be performed Realistic and measurable force impact on the case at room temperature as well as cold and hot temperatures Submersion in a variety of materials dirt sand rock as well as submersion in water Shock and vibration tests at realistic g forces with a circuit encapsulated within the case to test the functionality of a circuit in the rugged conditions that may be encountered 5 6 Battery Unit Level Test Cases To verify their functionality at the extreme temperatures we would test the battery s properties while using a temperature chamber By starting at 80 C and decreasing the temperature by 5 C every ten minutes we can take a reading to test the voltage and current This will help us get an idea for the temperature at which the battery functionality becomes unreliable 5 7 Power Supply Circuit Unit Level Test Cases Verify the power supply circuitry through the following test cases e There is no short to ground on any power line A3 3V line is properly regulated 5 line is properly regulated Alllines can supply current defined in
103. TD7 LATD7 LATD7 LATD7 samples on lower edge data bit 17 i ktt transciever to turn off the readback LATBbits for j 0 LATB2 j lt 2 0 j Wireless Bear Tracking Group May1010 Page 175 LATDbits LATD7 3 for k 0 k lt 37 k Turn off data and clock pins LATBbits LATB1 0 LATDbits LATD7 0 return data Reads back the AFC values from the tranciever Only valid during reception of FSK signals The Freq in Hz is given by the following Freq RB Readback Demod 1 2 18 In the absence of frequency error Freq RB 100kHz Note for a valid result the down converted input signal must not fall outside the BW of the analog IF filter float VHF_AFC_RB void long reg val 0x107 signed long RB Value 0 float constant 7 69043 demodulation CLK 2 18 where demodulation CLK 2 016 MHz RB Value VHF read back reg val return RB Value constant Reads back the Silicon Revision of the transciever long VHF Silicon Rev RB void long reg val 0 1 7 return VHF read back reg val Reads back the RSSI of the transciever signed float VHF RSSI RB void long reg val 0x147 long data 0 char RSSI 0 I gain 0 LNA 0 char gain correction data VHF read back reg val RSSI Ox7F amp data masks the RSSI readback to only retreive the RSSI level information I gain data gt gt 7 amp 0x03 ge
104. The inner wire left exposed will be equal to approximately wavelength of the transmitted signal The coax can be then directly mounted to the PCB with the appropriate connector The PCB will need to be a 4 layer board in order to receive the necessary grounding capabilities for the best antenna performance The router antenna will be the Yagi antenna because of its easy of construction and ability to better withstand the elements than the axial mode helical antenna There will be three or more element Yagi antennas and just as many separate antennas in the system in order for the antenna to view all directions Using the link budget equation at the beginning of this section we can determine the amount of power that will be delivered to the router from a bear i3 Pr PrGrGr R TOTOR Gen In the system that we will use the PT will be equal to 1 Watt The GT is the gain of the ideal omnidirectional whip antenna which by definition is 1 The GR is the gain of the router antenna which we will estimate to be 10 dB or a numerical gain of 3 2 The wavelength at 217 MHz is 1 38 meters We will assume that the distance needed to transmit is about 8 km A compensation factor of 1 2 is placed in the equation as well to account for terrain and tree obstructions 1 38m 1 Pp 3 01E 1 Watts At baud rate of the system the receiver can sense at levels down to 130 dBm or 1E 16 Watts The receive
105. Wireless Bear Tracking System Final Document Clients Digi International Wildlife Research Institute Faculty Advisor Dr Ahmed Kamal Team Members Zach Bruce Blane Chesnut Chris Donnelly John Pritchard Adam Rasmussen Forward This document includes information about every aspect of the 2010 Senior Design Project for group 10 Wireless Bear Tracking This document was pieced together over a two semester period and includes information about the design and then the implementation This project will need to be completed in another phase of the project so this document will be important to understand the progress of the project The main sections of the document are Introduction Design Requirements Approach and Product Design Implementation Test Cases Schedule and Resources The approach section details all of the possibilities for the design that were researched including the actual design that was selected The implementation section discusses the completed prototype and what parts were finalized as well as any PIC code explanation The test case section details the different testing procedures that were used to verify the system as well as the results from those testing procedures The table of contents follows as an outline to the document Wireless Bear Tracking Group May1010 Page 2 Table of Contents 1 UU c 13
106. ad to create two transmission lines because we were not able to keep transceiver and RF switch as close as possible Using Advanced Design System s ADS LineCalc and the characteristic of our PCB as shown in Table 6 we were able to calculate that a 50 ohm transmission line had a width of 109 mils PCB Material FRA H 64 mils Er 4 8 Mur 1 5 8 10 3 9x10 T 1 4 mils Table 6 PCB Characteristics Once we had the RF portions layout using the least amount of traces we laid out the rest of the PCB trying to make the board as compact as possible and avoid breaking up the ground plane Plated through holes were also added at various areas to connect the top and bottom ground planes We also kept all the external connecters on the same side Copper areas were used on each of the three buck converters to help with dissipating heat Using the large copper areas was suggested by the manufacturer The transceiver and power amplifier both have ground planes underneath of their packages which are used for RF performance along with helping dissipate heat We used copper areas to make these connections Once we had the layout done we used Advanced Circuits www 4pcb com to manufacture our circuit board because they have a special offer where we can build our boards for 33 each with no minimum quantity It should be noted that after we made these boards we realized that we inadvertently did not add the
107. als In our case the size required and space it takes up exceeds what we are hoping to fit inside of our case The base of the helix antenna is greater than 40 centimeters in length the circumference of the helix antenna is 19 centimeters and the height is nearly 40 centimeters as well While one of these would be simple enough for us to build ourselves the sizing of the unit exceeds our devices sizing constraint Gulley 3 6 2 Passive GPS Patch Antenna In an effort to try to keep costs low the next possibility for a GPS antenna was the passive GPS patch antenna With this solution we could either design and build our own again or buy one from another manufacturer The advantage of the passive GPS patch antenna is that no additional power is used in locating and getting a fix on GPS satellites The disadvantage of a passive antenna versus an active antenna is that it can take longer to find the GPS satellites requiring the device to be powered on longer and therefore using more power anyway While a passive GPS patch antenna would be simple to design and print on to a printed circuit board it requires a larger size because the dielectric material is air Most manufacturers use a different dielectric material in order to reduce the size of the antenna Therefore it would be beneficial to use a manufactured GPS antenna unit rather than an antenna we would build ourselves The cost of purchasing an antenna is less than 15 per unit Going with
108. als and financing necessary to complete the project Prototypes will be available by April so the bears can be collared after they have left hibernation There will be three collar units and two router units available to test The mechanical design and the computer mapping interface are not the focus of this stage in the project In the future these may be developed by another senior design team or engineers at Digi 1 2 Acknowledgments Digi International is going to supply all of the necessary parts and funding for the project This is a non profit task that they have decided to support and are going to help with any aspect of the product They will provide technical assistance as needed Technical expertise has been provided by James Puzzo Jordan Husney Mark Tekippe and Jim Stroner Technical expertise has been provided by ISU Faculty including Dr Ahmed Kamal Dr Nathan Neihart Dr Jiming Song Dr Mani Mina Leland Harker and Matthew Nelson Wireless Bear Tracking Group May1010 Page 14 1 3 Problem Statement Black bears need to be tracked live from a remote location The area of concern will be approximately a 25 mile by 10 mile plot It is difficult to transmit a signal in this area due to dense foliage A collar unit must be developed that can transmit tracking data every ten to fifteen minutes This unit must be smaller than the current unit and ideally have a battery life of six months It is also important that the collar b
109. also has a gain of 16 dB This antenna also comes with a coaxial cable connection This will be able to connect directly to a connection on the GPS chip that we will include 3 7 Microcontroller Several types of controllers were considered but PIC was chosen over others such as Atmel a processor because of the great combination of versatility and ease of use The microcontroller chosen was the PIC18F46J11 This basis for this choice was its low power features multiple communication ports large program memory I O count and price It is an 8 bit microcontroller of the PIC18 family 16 bit and 32 bit controllers were considered but it was found that 8 bit would be sufficient Choosing 8 bit restricted the choices to the PIC 10 12 16 and 18 families There were several controllers among these families that suited the needs of the application but there were limited availabilities The controllers that were best suited and readily available were among the PIC18 family The PIC18F46J11 was found to meet all essential needs with the exception of EEPROM This was compensated for by selecting an external EEPROM chip 24FC512 manufactured by Microchip Wireless Bear Tracking Group May1010 Page 54 C programming was chosen again due to versatility and ease of use There are other easier languages to use such as PICBASIC but it would limit the functionality of the controller as well as efficiency There are more efficient low level language
110. alues are used for asyncrounous transmission long reg_1 0x21A1091 0x21B9011 CP high current 0x21A1091 clock 0x21A1011 no clock long reg 3 0x28A34883 long reg 0 0x11AEA140 0x11AFFFFO 0x11AEA140 195 MHz long reg 2 0x22749BC2 0x2277FBC2 max power 0x22749BC2 0 dBM long reg 6 0 3661 6 long reg 5 5 long reg 0 RX 0 59 140 digital lock ready 0x99AEA140 long reg 4 0x8010CA14 k 10 dis BW 50 0x8011AA94 k 21 Wireless Bear Tracking Group May1010 Page 157 long reg 10 0x4B97043A 0x3C97043A 30 kHZ 0x3297043A MAX AFC at 25kHZ 0x4B97043A AFC at 37 5kHz long reg_15 0x4000F for testing purposes only These register values are used for Syncrounous transmssion See Final Document for Details in the values These registers are used for both TX and RX long reg 1 0x21A1091 0x21B9011 CP high current 0x21A1091 clock 0x21A1011 no clock long reg 3 0x28A34883 these register are used for TX only long reg 0 TX 0x1AEA140 regulator ready on mux out 0x11AEA140 195 MHz 0x1B00000 no factional N value long reg 2 0x43A5B82 not inverted fdev 8 30kHz 18 power 0x22725B82 inverted power 18 0x22749B82 inverted 36 power 0x22749B92 36 power Guassian 0x22749BD2 inverted raised Cosine 0x225C9B92 inverted Guassian with FX devivation 0 25 300 75 0x22749B82 These Registers of used f
111. anged every week Still the researchers prefer the live location data to the old VHF system Digi International has taken the task of providing a new collar for the researchers as a non profit project They are supporting the project financially and through their technical expertise and advice The goal of this project is to create a new collar that will continually and reliably send location data to the researchers This unit must run on battery for at least 6 months and transmit location about every fifteen minutes It is also important to make the unit durable and smaller than the current SPOT units Wireless Bear Tracking Group May1010 Page 13 The collar will consist of the basic building blocks of GPS transceiver microcontroller and power electronics as shown in Figure 5 The collars will transmit their GPS location via frequencies to various router units units will transmit on the same frequency 217 MHz and the system will use a time division multiplexing network scheme The router and collar units will have similar hardware with minor differences in the VHF antenna and battery A home base router will output the data serially to be easily plotted as data points on Google maps or similar mapping software The current units are very expensive nearing 2000 The units we are developing will be much less expensive Estimated unit cost is around 290 Digi International is providing all of the materi
112. antenna would be incorporated into the collar and possibly directly into the unit itself It would be difficult to keep the antenna oriented in the correct direction due to its size Pros e Antenna is inexpensive e Size is much smaller than other antennas e Hasahigh antenna gain compared to the 4 wavelength antenna Impedance can be matched using discrete components e The ground plane will not be directly perpendicular to the antenna which may lead to interesting results e Antenna is not available in size from a manufacturer e Difficult to manufacture uniform antennas for collars e Difficult to orient antenna on collar for maximum reception 3 4 5 Rotating Directional Antenna The previous antennas have been designed for use on the collar The following antennas will be of use on the router unit These antennas will need to have much higher gain and therefore will not be omnidirectional The directional antenna allows there to be higher gain over a more condensed area yet it is necessary to receive signals from all directions as bear can be traveling at any position One option is to build a highly directional antenna and have it rotate to pick up signals in all directions using a small motor This would allow there to only be one antenna on the router with high gain and it would receive from all directions horizontally Pros Antenna is very directional and has high gain There will be less antenna components than other router an
113. appropriate network for transferring the information from routers back to the home router This section describes that registration and initial set up The router registration will execute the following Router will find the nearest adjacent router in the direction of the home base Router will know how many routers the information will transfer through to arrive at the base router This will determine the router number Router will define its time slot based on its router number Router should know physical location of all other routers in system With this information the steps that will be taken for the router registration are as follows The home router hardcoded as Router 401 will be registered as Router A Router will send out a signal asking that all appropriate routers register along with the time the signal was sent Any router that receives the signal will wait a certain number of seconds based on the individual router number and then send the unit s GPS location This allows Router A to store the GPS coordinates for the routers within range Once the number of router time slots has passed Router B will do a similar process This will once again allow Router B to know all of the GPS coordinates for the routers within range This process will continue in an avalanche type of process until each router knows the location of all of the other routers Wireless Bear Tracking Group May1010 Page 28 Because the location of
114. ata Bit 0 bits 11 for j 0 k k Data bits 9 for j k Data bits 8 for j k Data bits 7 for j k Data bits 6 for j k Data bits 5 for j k Data bits 4 for j k Data bits 3 for j k Data bits 2 for j k Data bits 1 for j k Data bits 0 for j k Data release enable pin LATBbits 0 k lt 37 for k LATB2 1 k Data Bit bits 10 for j Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 Bit 0 procedure for reading back the data Data is outputed on the raising edge of the clock Data is read on the lower edge of the clock The first bit outputted must be ignored for i for j 0 LATDbits LATD7 3 lowers the SLE and performs one more clock cycle to allow the 0 1 lt 18 1 j lt 2 if j 0 amp amp 1 gt 1 and skips the first two iteration for k data bit data data 0 k 37 PORTBbits RB0 j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits j LATDbits delay LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LATD7 LA
115. ata transmission only then the time needed for each time slot is 175 bytes x 9 bits byte 2 05 ms 5251 d 300 bits sec Nine bits per byte is used to account for the parity bit If each frame is 10 minutes long the number of time slots available is 10min x 60 sec min 114 5 251sec Wireless Bear Tracking Group May1010 Page 26 it is shown that there 114 time slots in a length of time equal to 10 minutes Each collar is given three time slots in order to achieve a successful transmission If the first attempt is successful the collar will sleep for the additional two time slots it is assigned If each collar uses three time slots this allows for 38 collars in this static case of the system As location must arrive at the home base every fifteen minutes the last five minutes of the TDM allows for router to router communication A later section defines how the routers register with each other to transmit the information to the home base Routers will relay their unit information forward to the home base in a chain until the home base has received all of the data The time slot for each router is assumed to be the worst case scenario where it must send location information for all 38 collars After the routers have relayed the information to the home base the 15 minute TDM cycle will repeat 3 2 3 5 Time Slot Recognition Assigning a time slot to a unit is a simple programming task
116. b01001 0b10100 0b10101 0b01010 0b01011 0b01110 0501111 0510010 0510011 0510110 0510111 0511010 0511011 0511100 and encodes it into 4b 5b Wireless Bear Tracking Group May1010 Page 185 051111 encoded message 0511101 break default encoded message 0b00100 return encoded message The procedure takes in the 4b 5b encoded message and decodes it back to its true 4 bit message long decode message long encoded long decoded message 0 Switch encoded message 0511110 decoded message 050000 break case 0b01001 decoded message 050001 break case 0b10100 decoded message 050010 break case 0b10101 decoded message 050011 break case 0b01010 decoded message 050100 break case 0b01011 decoded message 050101 break case 0b01110 decoded message 050110 break case 0b01111 decoded message 050111 break case 0b10010 decoded message 051000 break case 0b10011 decoded message 051001 break case 0b10110 decoded message 051010 break case 0b10111 decoded message 051011 break case 0b11010 decoded message 051100 Wireless Bear Tracking Group May1010 Page 186 break case 0b11011 decoded message break case 0b11100 decoded message break case 0b11101 decoded message break default decoded message 0b1101 0b
117. cal Hardware 31 days 10 5 09 Mon 11 16 09 Embedded Programming 31 days 10 5 09 Mon 11 16 09 Software Interface 31 days 10 5 09 Mon 11 16 09 Chassis 11 days 11 2 09 Mon 11 16 09 End Product Prototype Development 76 days Mon 11 16 09 Mon 34410 Acquire Materials for Prototype 41 days Mon 11 16 09 Mon1 11 0 Assemble Prototype 36 days Mon1 1 10 Mon 3440 End Product Testing 121days 11 2 09 4 19 10 Test Planning 11 days 11 2 09 Mon 11 16 09 Test Development 16days 1 1 10 Mon 24410 Test implementation 55 days Mon 2440 44840 Presentations 158 days Thu 9 24 09 5 340 Project Plan 4days 9 24 09 Tue 9 29 09 Design Review Bdays 11 9 09 Mon11 16 09 6days 44240 Mon 44940 Industry Review Panel 11 days 4 19 10 Mon 5 340 Product Documentation 158 days Thu 9 24 09 Mon 5 340 Project Plan 12days Thu 9 24 09 Fri 10 9 09 Design Document 11 days Mon1146 09 Mon 11 30 09 Project Poster 11 days 3 29 0 Mon 441240 Project Final Report 156days 44240 Mon 5 340 Weekly Status Emails 158 days Thu 9 24 09 Mon 5 340 Figure 48 Schedule for Project Page 125 Wireless Bear Tracking Group May1010 10 Closure Material Outlined in this section is the contact information of the client faculty advisor and student team The closure material also contains a brief summary of the project pla
118. cemuteatesessaates 46 3 4 5 Rotating Directional Antenna M CUM SNO tpa 47 3 4 6 Helical Antenna Array seas ceovesisssusiesesnavcssaanavaatasuavesvabdageaseantunssastavadvashavasmaaeeseneantenss 48 247 Yagi Antenna ATAY seereis TEE 49 2r CEP opo M 50 5 GPS M 52 3 6 GPS 52 30l UR UFU ere D EN OS ERAT a 53 3 6 2 Passive GPS Patch 53 3 6 3 Active GPS Patch 54 304 Detailed eae aaa eae ae 54 SJ 55 IMEEM DEC 54 Dede CASSIS e 55 Bede Commercial Cases ioco etico Me MEN redi 55 382 Ind strial CE CERE DOO UESTRE 56 3 08 32 Detaled bo o MC 56 3 9 Power Supply Circuitry Lice ean NER ERU F DRM BY A QU KCl VE UB X QU 57 3 91 Linear D 57 39 2 SWitching Bosnluolsocstoes medido editi mt dp 58 3 9 3 Detaled Desi oily
119. cking Group May1010 Page 48 3 4 7 Yagi Antenna Array An antenna array can be made similar to the helical antenna described above but it can be made with a Yagi antenna A Yagi antenna consists of a simple dipole antenna along with several conducting directing elements and a reflecting element The Yagi antenna can vary in gain based on the length of the elements and the number of elements but Yagi antennae consistently can have gains for 8 to 11 dB More antenna elements will increase gain but also decrease directivity resulting in more antennas necessary to cover the pattern Burberry The Yagi Antenna can be constructed out of very simple materials including conducting rods and PVC or other plastic tubing Below is an example of a Yagi antenna Figure 19 Six Element Yagi Antenna Setian Pros e Antenna is inexpensive e Antenna can be easily constructed e Gain is higher than most antennas can be as high as 11 dB e Antenna will withstand the harsh environmental conditions Impedance can be matched using discrete components e High gain is achieved at the cost of directivity Antenna may consist of several different components Wireless Bear Tracking Group May1010 Page 49 3 4 8 Detailed Design The bear communication solution will consist of a 14 wavelength whip antenna and a Yagi antenna array solution The wavelength antenna will constructed from a coaxial cable with the outer casing stripped back
120. cksum Decode The checksum is how the receiver checks the validity of the data it receives It computes the checksum by taking the last 12 bits of the received decoding 10 of those bits and shifting the other 2 bits to the most significant positions Wireless Bear Tracking Group May1010 Page 100 5 System Unit Level Test Cases The following section defines the test cases to which the design will adhere There are unit level tests to confirm the individual components capabilities as well as system level tests to confirm that the overall bear tracking system will meet requirements 5 1 VHF Transceiver Unit Level Test Cases Impedance matching will be tested between the RF output of the transceiver and input of the external power amplifier Impedance matching will also be checked between the output of the external power amplifier and the antenna port The external oscillator will need to be measured to ensure that it is oscillating at the desired frequency If the oscillation frequency is high the load capacitors should be increased to lower the frequency If the frequency is low the load capacitor values should be decreased Writing and reading to the registers of the transceiver from the microcontroller will also be tested to ensure the microcontroller is able to configure the transceiver The output RF spectrum will be tested at the output of the transceiver and at the antenna port The spectrum will be checked to make sure t
121. configuration else return 0 Go to Sleep function go to sleep desc This function is called after a decision is made about the type of wakeup either normal POR or from deep sleep Within this function is a sleep counter that allows versatile Sleeping period The postscalars for the watchdog timer have only a certain set of sleep periods so the sleep counter increments those periods m void go to sleep void unsigned int config 0 sleep count This function increments the sleep counter e g 5 seconds can be acheived with about 151 increments of a 33ms sleep time while 1 Write DSGPR countl count2 Save the counter data before deep sleep config DPSLP_ULPWU_DISABLE DPSLP_RTCC_WAKEUP_DISABLE configure deep sleep wake up sources GotoDeepSleep config This function puts the device into deep sleep return Miscellaneous Functions functions blink led sleep count gps parser send eusart send gpio batt chk Wireless Bear Tracking Group May1010 Page 165 desc This function is called after a decision is made about the type of wakeup either normal POR or from deep sleep Within this function is a sleep counter that allows a versa
122. control ack bit eeprom control 0xA0 ack bit 1 while ack bit 1 IdleI2C2 ensure module is idle Wireless Bear Tracking Group May1010 Page 195 StartI2C2 initiate START condition while SSP2CON2bits SEN wait until start condition is over load EEPROM control byte in buffer lt 7 4 gt 1010 lt 3 gt address block 0 lt 2 1 gt hardware defined address 00 in this case lt 0 gt 0 for write WriteI2C2 eeprom_control write 1 byte R W bit should be 0 IdleI2C2 ensure module is idle ack bit SSP2CON2bits ACKSTAT return Function eeprom read Params address block either 1 or 0 for the page of the memory address the address of the memory rdptr Character type pointer to PICmicro MCU RAM for storage of data read from I2C device length Number of bytes to read from I2C device Returns none Description read from the EEPROM EMANUELE N M void eeprom read unsigned char address block unsigned int address unsigned char rdptr unsigned char length unsigned char eeprom control high address low address data IdleI2C2 ensure module is idle StartI2C2 initiate START condition while SSP2CON2bits SEN wait until start condition is over load EEPROM control byte in buffer lt 7 4 gt 1010 3 address block s
123. d USB LED is lit e On computer find the port that the FTDI chip uses as virtual com port Connect to found serial port with putty 2400 baud e Send to enter debug mode e Turn 3 3v line on with b option e Enable transceiver with f option e Put in transmit mode with 1 option 5 Tests observed I observed the setup of the system to transmit as outlined in the System Setup section I also observed a picture of the radio spectrum that they are operating on collected by a spectrum analyzer They have also seen successful modulation of data and the transceiver successfully demodulate the data have verified that the power supply has a voltage ripple of less than 50mV P P which is within specifications of chosen transceiver The group has had successful writes to the external EEPROM memory chip Wireless Bear Tracking Group May1010 Page 130 6 Critique 6 1 Strengths and Weaknesses e Programmed debugging functionality into microcontroller code e Careful layout of component sections in prototype board e Could be hard to debug some features e Implementing media access control manually 6 2 Does the Implementation Meet Specification Of what the group has accomplished so far I believe that they are within spec They have included all the necessary hardware to fulfill the requirements of their project However it is to earlier in the project as a whole to tell if what they will do in the future will be able to fulfill t
124. d power even with the compensation factor is much above the transceiver s ability to receive Wireless network propagation simulation software called Radio Mobile is available free online and used by many amateur network designers to test the connections and transmission characteristics of the wireless signals This software uses a model for radio propagation called the Longley Rice model The software allows land cover and elevation data to be mapped in the system and simulate the actual terrain for the devices Wireless Bear Tracking Group May1010 Page 50 The area of land that the bears will travel between Ely and Tower Minnesota is loaded into the program along with the characteristics for the router antenna and the collar antenna The calculated radiation pattern antenna gain line loss transmission power and antenna sensitivity all factor in to the outcome of this model Figure 20 below shows the map of the terrain and then three units Two of the units are to simulate bears and the third unit will simulate the router In Figure 21 you can see the Router unit transmit its signal and you can see that in this simulation the coverage of one router unit nearly covers the entire area at one watt of transmission Figure 20 Radio Mobile Area of Concern Wireless Bear Tracking Group May1010 Page 51 Figure 21 Radio Mobile Router Station Propagation 3 5 GPS Module The GPS Module chosen was the Ublox NEO 5Q This was chose
125. e 34 all show the circuits used in ADS and their corresponding simulations i 1 0603 ECJZ Cla T E A cM none ubste M Sub1 _ 3 cies om partName ECJZEC10101J 32 0 mil Value 68 nH L 71 0 mil mil E le t11 AREE Y DC 3 PartNumberzE QG18HN10NJOD SRC2 p Value 10 nH EX Sus MSub muy soos 19018 RIF yy W 28 0 mil ieee Ci WC PC Subst MSub1 PattiuribeLao iei s gs CE wes2omi wei2gmi Tem d L 78 25 mil L 140 0 mil Tem4 rut x L 78 25 mil 140 0 mil up ae E partNaine ECJZECIET00D 3 2 159 75 53 16 Mi ra Oey ee muRata oe a s ss ss s s s s s s MBUB Medellnclude Panasonff UR e qe MSub1 Panasonic Models 7 o no o t o c 0 CU Td Magie P MERE ME Murz1 Cond 5 8E 7 Hu 3 9e 034 mil T 1 4 mil Rough 6 mil Figure 31 Transceiver output matching network simulation circuit with non ideals Wireless Bear Tracking Group May1010 Page 80 Reverse Transmission dB Output Reflection Coefficient E 5 1 m3 freq 217 0MHz 2 dB S 4 4 23 041 dB S 4 3 0 387 a3 245 e 5
126. e individually identified and easily removed 1 4 Operating Environment The unit will be exposed to the harsh conditions of northern Minnesota Temperatures range from 30 to 70 C The unit must be waterproof and weatherproof The collar must be comfortable on the bear or the bear will tear the collar off The bear cubs also get restless during the hibernation months and will proceed to chew and destroy the collar The collar unit must also be easily handled by the researchers They must be able to simply remove and ID each unit The researchers are not as familiar with complicated technologies and the unit must be as user friendly as possible 1 5 Intended Use and Intended Users The intended use for the product is to track black bear mothers in a 25 by 10 mile area The collar must function in this area and if successful it can be transferred to other wildlife tracking areas as well The collar will function properly in very dense forests The intended users are the bear researchers at the facility in Ely Minnesota These researchers are Sue Mansfield and Lynn Rogers 1 6 Assumptions There are many assumptions taken into account when working on this project It is difficult for us to gain access to the forested area so we must assume how certain signals will react to the forest We assume that the GPS signals will reach the collar if the collar is properly located on the bear We also assume that lower frequencies will penetrate the
127. eck of the bear Also the researched designs include the total length to be around 2 wavelength which is difficult to keep contained inside of the collar Pros 3 4 4 Radiating element amp coaxial inner conductor Coaxial outer conductor N Metal sleeve Dielectric insert Mobile terminal case Figure 17 Sleeve Dipole Antenna Saunders and Aragon Zavala Antenna is inexpensive More reliable impedance matching than alternative antennas Coaxial transmission line will give more accurate results Has a high antenna gain compared to the wavelength antenna Antenna will protrude out of collar and be subject to damage by the bears The curvature of the antenna will not allow for the ground plane to be perpendicular to the antenna and possibly allow interesting results Antenna is difficult to make and more expensive than alternatives Antenna sleeve length and style is difficult to measure and calculate Normal Mode Helical Antenna A helical antenna is a coiled antenna that allows the antenna size to be compressed The electrical length of the antenna is still half wavelength but the physical length of the antenna is much less than that This antenna in the normal mode will radiate out normal to the axis of the antenna It operates in normal mode when the diameter of the antenna is much less than that of the wavelength of the receive signal Wireless Bear Tracking Group May1010 Page 46 This
128. edule consists of all the tasks and subtasks from Section 8 2 The schedule was produced to ensure an on time completion of the project 9 1 Resources Based on initial research and our conceptual diagram we estimated the unit material cost to be 210 see Table 28 The unit material cost represents more of a worst case scenario of having to use more expensive technology to achieve the performance In the design stage we hope to reduce the single unit cost The material costs will be covered by the client Table 28 Single Unit Estimated Cost Item Estimate Cost VHF Communication 22 00 VHF Antenna 5 00 GPS 100 00 GPS Antenna 11 00 Battery 6 00 Microcontroller 17 00 Connectors 7 00 Printed Wiring Board 33 00 Power Electronics 9 00 Total 210 00 The development labor hours required to complete the project was 1069 hours see Table 28 With an hourly rate of 20 per hour the development labor cost for the project is 21 380 However for this project our team will donate the development labor cost The total cost for the project is 21 800 The total cost includes building two prototypes see Table 29 Table 29 Project Costs Description Estimated Unit Cost Estimated Qty Extended Cost Prototypes 210 00 2 420 Development Labor Costs 20 00 1069 21 380 Total 21 800 Wireless Bear Tracking Group May1010 Page 123 9 2 Schedule A schedu
129. eginning and end of the frame thus resulting in 2t The lower the baud the less number of time slots are available Lower baud usually results in lower BER and better penetration through the dense woods The higher the baud the greater number of time slots available Higher baud usually results in higher BER and does not allow the signal to penetrate dense forestry as well So in selecting the proper baud tradeoffs need to be considered The number of bits per transmission should be static 3 2 3 4 Specific Unit Data Communication The specific data needed by the router from the unit could be the following preamble data start string UnitID MAC data flags CRC data end string The preamble will consist of 6 bytes of alternating ones and zeros The purpose of the preamble is to all the transceiver to synchronize with this incoming message Data start string is a unique set of characters that differentiates this message from any other message UnitID is the unit s identifier which can be changed in software MAC is the unit s unique MAC address this is hardcoded and will never change Data is the information required to locate the bear Flags are the bytes needed to let the router know the status of the unit CRC is the data needed for bit error checking and Wireless Bear Tracking Group May1010 Page 25 correcting Data end string is the set of bits that lets the router know it has reached the end of the message The unit w
130. eiver and EEPROM will take place This is where communication with other units will take place one frame in Wireless Bear Tracking Group May1010 Page 86 network After all networking logic is complete data is written to the deep sleep save registers and the PIC goes back to sleep 4 3 2 1 3 maintenance This function performs maintenance on the peripherals of the PIC Its purpose is to make sure all devices are working correctly 4 3 2 1 4 tx test This function runs the procedure needed to put the section in transmission mode This is used for testing purposes 4 3 2 1 5 rx test This function runs the procedure needed to put the VHF section in reception mode This is used for testing purposes 4 3 2 2 init c This file contains functions that initialize communication ports I O ports the oscillator etc 4 3 2 2 1 eusart2USB This function remaps EUSART2 pins Rx2 and Tx2 to pins 14 and 15 respectively This allows the FTDI USB to Serial converter chip to talk to the PIC 283222 syc eusart2VHF This procedure sets up the reprogrammable pins needed VHF transmission or reception In TX mode USART 2 clock and data lines are mapped to Pin 1 and Pin 44 of the PIC respectively In receive mode external interrupt 1 and 2 are programmed to Pin 4 and Pin 1 respectively Interrupt 1 is used to detect when the VHF SWD INT goes high and external interrupt 2 i
131. ele Sut ta 185 Appendix 21 PIC Code encoding h 193 Appendix 22 PIC Code e amp prorti 126 6 aa ue rine 194 Appendix 23 PIC Code eeprom _12 2 22 199 App ndix 24 PIC Code gps 126 201 Appendix 25 PIC Code gps 1201 207 Appendix 26 PIC Code 209 Appendix 27 PIC Code blox Duci iei eoe ort 217 Appendix 48 PIC Code Tedd E 214 Appendix 29 PIC Code _ e m eB editi dun beh ma eiua DUM eA 218 Wireless Bear Tracking Group May1010 Page 10 Definitions ACK Acknowledgement ADC Analog to digital conversion AFC Automatic frequency control ASK Amplitude shift Keying BER Bit Error Rate bps Bits per second CRC Cyclical Redundancy Check CSMA CA Carrier sense multiple access with collision avoidance dBm Decibel referenced to milliwatts ESR Effective Series Resistance FCC Federal Communications Commission FM Frequency Modulation FSK Frequency shift Keying GPS Global Positioning System I O In
132. electing Programmer Connect Build the project by selecting Project Build Program the microcontroller by selecting Programmer Program Unplug the programmer cable from the board Plug in the 6V DC power cable Verify the board has power by observing the small green LED Plug the USB cable into the board Open a terminal program such as HyperTerminal or Putty on the computer Look up the COM port of the USB on the computer Set the speed in the terminal to 2400 Baud Log in to the PIC by sending three characters menu presented shows the various commands that can be sent to the controller start transceiver mode turn on the 3 3V line by selecting option b Verify the 3 3V line is on by making sure he green LED near it is on Enable the transceiver with option f Set transceiver mode with option m Testing After the board was assembled important traces were observed using the oscilloscope to verify the behavior was correct The oscilloscope was also used to ensure the transceiver was properly modulating and demodulating data The power line was tested to make sure the ripple was within 50mV peak to peak also using an oscilloscope The antennae connector was hooked up to a spectrum analyzer to test the functioning of the transceiver 6 Project Critique The projects strengths were e The design is thoroughly documented e The sytem was designed in a modular fashion with each subsytem
133. ent of the product 8 7 2 Subtask 7 2 Design Document Development The objective of Subtask 7 2 15 to create a document that explains the design of our end product The design document describes the logic of our design how we plan to build our end product and how the end product will operate Wireless Bear Tracking Group May1010 Page 121 8 7 3 Subtask 7 3 Project Poster The objective of Subtask 7 3 is to create a poster to show the development of our end product It will show the problem our solution and the effort in developing the solution 8 7 4 Subtask 7 4 Project Final Report Development The objective of Subtask 7 4 15 to create a final document that records the end product in both final design and functionality 8 7 5 Subtask 7 5 Weekly Status Email The objective of Subtask 7 5 is to send a weekly status email to all members of the team our advisor and the instructors of Senior Design The emails will include the team s progress for the week meetings held during the week plan for the upcoming week and individual hours worked on the project for the week Wireless Bear Tracking Group May1010 Page 122 9 Resources and Schedule We estimate the single unit material cost to be 210 and development labor cost to be 21 380 The development labor costs are being donated by the team and the material costs are being covered by the client Section 9 2 outlines the schedule of the entire project The sch
134. es using off Table 9 off 2 1 mA power up external NO Set to 1 0 75mA crystal Table 15 RX Register 1 value See Section 4 1 3 1 Transmit Mode for details 4 Wait at least 0 7 ms 5 Write to Register 3 Transmit Receive Clock Register 00 1010 0010 1000 1101 0010 0010 00 0011 SEQ CLK CDR Clk DEM CLK BBOS Clk Address Divide 10 Divide 40 Divide 210 Divide 2 Divide 4 Table 16 RX Register 3 value See Section 4 1 3 1 Transmit Mode for details 6 Write to Register 6 IF Fine Cal Setup 0 11 011 0011 0000 1111 00011111 1 0110 IR Cal IF Cal IF Cal IF Cal Enable IF Address Source Source Dwell Upper Lower Fine Cal divide 2 Drive Time 51 Tone Tone OFF Level Divide 15 Divide 31 High Table 17 RX Register 6 value The ADF 7021 has an intermediate frequency IF bandwidth calibration which should be calibrated on every power up in receive mode to correct for errors in the bandwidth and filter center frequency due to process variations There are two different calibrations available Coarse and Fine Calibration In the cases where the receive signal bandwidth is very close to the bandwidth of the IF filter it is recommended to perform a fine filter calibration every time the unit powers up which is the case in our design IF Fine calibration is setup in Register 6 and is started by writing to Register 5 Wireless Bear Tracking Group May1010 Page 74
135. from handler c global var init return gt this function sets the required oscillator registers void osc init void Wireless Bear Tracking Group May1010 Page 156 OSCCONbits IRCF2 datasheet 1 these three bits control osc freq see OSCCONbits IRCF1 1 bits 111 equate to an 8MHz osc freq OSCCONbits IRCFO 0 bits 110 equate to an 4MHz osc freq return gt this function sets the required input output registers void io init void TRISBbits TRISBO 1 NHF Read Line TRISBbits TRISB1 0 VHFW Line TRISBbits TRISB2 0 VHF_SLE Line TRISBbits TRISB3 0 VHF_CE Line TRISCbits TRISCO 1 NHF MUXOUT Line input TRISCbits TRISC5 0 5 Shutdown Line TRISDbits TRISD2 0 3 3V Shutdown Line TRISDbits TRISD6 1 SWD INT Line TRISDbits TRISD7 0 NHF SCLK Line TRISEbits TRISEO 0 ANT_CTLO Line TRISEbits TRISE1 0 ANT_CTL1 Line ANCON1bits PCFG12 1 makes RBO a digital port and not an analog port LATCbits LATCO LATCbits LATC5 LATBbits LATB1 LATBbits LATB2 LATBbits LATB3 LATDbits LATD2 LATDbits LATD6 LATDbits LATD7 LATEbits LATEO LATEbits LATE1 return n wn n m ut mn This procedure configures the transciever eithr TX or RX mode by writing to the appropriate registers as defined in the Final Document void vhf init byte mode byte txrx_mode mode These register v
136. g val RRR k k k k k k k kk kk kk kk kk kk kk kk kkk kk kk kk kk Old Functions currently not in use S EEk k k k k k k k k k kk kk kk kk kk kk kk kk kkk kk kk kk kk void void eusartl init void eusart2VHF remap void Wireless Bear Tracking Group May1010 Page 161 Appendix 14 PIC Code datatypes h ifndef DATATYPES H define DATATYPES typedef unsigned char byte endif Wireless Bear Tracking Group May1010 Page 162 Appendix 15 PIC Code handler h file datahandler c author John Pritchard project Bear Tracker Project date Spring 2010 functions Desc This file contains all functions that handle data include pi8cxxx h include dpslp h include handler h include datatypes h include encoding h include init h include ublox read h include gps i2c h define ON 1 define OFF 0 define TX 1 define RX 2 define VHF 0 define USB 1 void reset _buff2 void define BUFFSIZE 50 Global variables int countl count2 These global variables are used in receiving the VHF data int VHF bit count 0 VHF byte count 0 keeps track of how many RX bits and bytes stored static byte VHF buff VHF BUFFSIZE Contains the RX data byte VHF buff end buff VHF BUFFSIZE byte VHF rx VHF buff pointer to the array unsigned char VHF data ready 1 polling variable to determi
137. ge Function ubx cfg msg off Params void Returns void Description Set the rate that a message is polled to 0 Function ubx cfg msg on Params void Returns void Description Set the rate that a message is polled to high as possible void ubx cfg msg on unsigned char class unsigned char id Page 92 CFG INF Sets which error messages are sent to the I2C lines For example Test Debug Notice Warning Error messages Function ubx cfg inf off Params void Returns void Description Disable all warning and INFormation messages void ubx cfg inf off void Page 94 CFG RST Can run a complete cold start or control reset the UBLOX chip Page 95 CFG DAT Set the datum seems more complicated than necessary Page 97 CFG TP Set the configuration for the timepulse output Will not need a timepulse because we can get exact ms times Page 98 CFG RATE How often is the GPS calculating a new location Page 99 CFG CFG Can save the configuration settings but there is no battery backup or flash or EEPROM memory Page 101 CFG RXM Set the unit into Eco Mode no Poll available This must be set after other settings Wireless Bear Tracking Group May1010 Page 212 101 Antenna control settings not sure which settings we need Page 102 CFG SBAS What extra tracking to use WAAS etc CFG NMEA sets the NMEA version not needed CFG
138. ha EEG Sn 1 Lines if we nct get the USART be properly ric 5 DD rcannct exceed 3 0 Wireless Bear Tracking Group May1010 Page 136 Appendix 5 GPS Revision Schematic GND CONDO COM INE GPEDGCKTC SOAS BCL2 Patt BOKP Vor HCTES gelect Jini gn h Y I rEnnid i be able to heandle7 Fin TOO Enit ripple Pin RxDi1 tobernal pull oe resiater te WE tolerant up to 3 6 Volts Pin internal pull of Ee WE Pin CPG GPS s t low always irdicatizg always in Eon Woda The LED indicated tHard volta cf 2 17 et lak whez Antenna nased zxE bs cosnected te pin P Retina anbsnnra draws 2 Heed for 0 Otm Resistor ZA cunzecbor Oba part Jb uo Wireless Bear Tracking Group May1010 Page 137 Appendix 6 Power Supply POWER SECTION Li ahould handle peak current rts need to be decopzlated aoerce used only Wall Jack 67 to 307 l iithiue or Alkaline te a e These parts need to be depopalated if external source GENERAL NOTES Do MOT USK NIMI BATTERIES PART NOTES d with NA21D1500L for availabli a recommended Layout have the positive voltage on the cated have forward voltage of 2
139. hat the frequencies outside of our 25 kHz bandwidth at our center frequency is below the FCC mask requirements Transceiver to transceiver communication will be tested Data will be send from one transceiver and read from another to ensure that communication has been made between the two units 5 2 VHF Antenna Unit Level Test Cases Each collar and router will be tested under ideal conditions and then it will be tested under conditions representative of operational use The router antenna will be as ideal as possible in the real application but the collar antenna will also be tested under different curvature settings as well as with a simulated bear to block signal reception Measure the input impedance of the antenna using a network analyzer The input impedance should be matched over the desired frequency range to minimize the reflection coefficient of the antenna Use the university s antenna lab equipment to measure the radiation pattern for the antenna Both the router antenna array and the collar antenna must be as omnidirectional as possible Wireless Bear Tracking Group May1010 Page 101 Collar antenna must easily flex around the neck of the bear without drastically affecting performance 5 3 GPS Module Unit Level Test Cases This section describes the testing process that will be undergone once the board has been fabricated The microcontroller will output data to a PC when needed The GPS chip will output data to the microco
140. he automatic frequency correction and outputs corrected frequency A frequency output of 100 kHz means there is no frequency errors The AFC when enabled automatically adjusts the value of the fractional n to get a frequency of 100 kHz The equation for the frequency read back is the follow equation where DEMOD is given from register 3 at 2 016 MHz AF CngApBACK DEMODc amp 218 7 69043 4 3 2 3 18 VHF Silicon Rev RB This function returns the silicon revision of the transceiver The current silicon revision is 0x2104 Wireless Bear Tracking Group May1010 Page 91 43 2 3 19 VHF RSSI RB This function reads the received signal strength indication RSSI value from the transceiver and returns the RSSI in dBm The signal strength in dBm can be calculated using the following equation Input Power dBm 130 dBm Readback Code Gain Mode Correction x 0 5 The readback code is the first 7 bits of the readback value The gain mode correction is given by the next 4 bits and gives a correction value based on the following table LNA Gain Filter Gain Gain Mode LG2 LG1 FG2 FG1 Correction H 1 0 H 1 0 M 0 1 1 0 24 0 1 0 1 38 M 0 1 L 0 0 58 L 0 0 L 0 86 Table 24 Gain Mode Correction Analog Devices 4 3 2 3 20 Filter Cal RB This function reads back the filter bandwidth calibration of the transceive
141. he other requirements such as range since it is currently to early to test 6 3 Suggestions I really admire this group and have little suggestions for them other than maybe they could have thought about using a transceiver that would have been easier to work with as far as media access control and such Wireless Bear Tracking Group May1010 Page 131 Appendix 2 Operations Manual Done by Jamin Hitchcock Wireless Bear Tracking Senior Design Group MAY10 10 Team Blane Chesnut Chris Donnelly Adam Rasmussen John Pritchard Zach Bruce Advisor Dr Ahmed E Kamal Client Digi Auhor Jamin Hitchcock 1 Overview Wireless Bear Tracking project s goal is to design a system to track the location of bears the wild The system uses GPS to determine the bear s location and a VHF transmitter to send data to recievers The system would be built into a collar worn by the bears 2 Requirements main functional requirements are that the unit must be able to recieve GPS data to determine the bears location The unit must be able to transmit that data to a reciever so that they can be used by researchers The battery life of the unit must be at least 3 months The unit must send location data to the reciever at least once every 15 minutes The physical dimensions of the device cannot exceed 3 7 x 2 6 x 1 3 Implementation So far a test board has been designed and assembled for the bear tracking unit The board consists
142. he prototypes and acquire these parts and materials This task also includes acquiring any necessary tools needed to build the prototypes 8 4 2 Subtask 4 2 Assemble Prototypes The objective of Subtask 4 2 is to build the prototypes and finish any embedded programming code and end user software At the end of this task we will have built prototypes that are programmed and ready for testing 8 5 Task 5 End Product Testing The objective of Task 5 is to create and implement tests to ensure the end product meets the necessary functional and non functional requirements 8 5 1 Subtask 5 1 Test Planning The objective of Subtask 5 1 is to create a list of tests necessary to ensure the end product meets the necessary requirements This task includes creating a list of necessary tools needed to perform the tests 8 5 2 Subtask 5 2 Test Development The objective of Subtask 5 2 is to create the test procedures and any test hardware and or software necessary to accomplish the tests defined in Subtask 5 1 8 5 3 Subtask 5 3 Test Implementation The objective of Subtask 5 3 is to use the tests created in Subtask 5 2 to test the requirements and functionality of the prototypes The test implementation includes any necessary debugging and modifying of the design in order to successfully fulfill the defined requirements Wireless Bear Tracking Group May1010 Page 120 8 6 Task 6 Presentations The objective of Task 6 is to make
143. hown as input to function lt 2 1 gt hardware defined address 00 in this case lt 0 gt 0 or write eeprom control 0 address block amp 0x01 lt lt 3 0x08 Writel2C2 eeprom control write 1 byte IdleI2C2 ensure module is idle load high byte of address into buffer high address address gt gt 8 amp 0 00 WriteI2C2 high address WRITE word address to EEPROM IdleI2C2 ensure module is idle load low byte of address into buffer low address address amp 0 00 Wireless Bear Tracking Group May1010 Page 196 1 for memory void e WriteI2C2 low address write HighAdd byte to EEPROM IdleI2C2 ensure module is idle StartI2C2 initiate START condition while SSP2CON2bits SEN wait until start condition is over WriteI2C2 eeprom control 0x01 WRITE 1 byte R W bit should be read IdleI2C2 ensure module is idle getsI2C2 rdptr length read in multiple bytes NotAckI2C2 send not ACK condition while SSP2CON2bits ACKEN wait until ACK sequence is over StopI2C2 send STOP condition while SSP2CON2bits PEN wait until stop condition is over return Function eeprom_write Params address block either 1 or 0 for the page of the address the address of the memory to write dataptr Character type pointer to data to write length
144. if dpslpevent 2 if wakeup source is from deep sleep fault do this FAULT RECOVERY LOGIC NEEDED change this else else return 1 Deep Sleep Source Checke functions dpslp chk desc This function is called after a decision is made about the type of wakeup either normal POR or from deep sleep It then determines the wakeup source It is supposed to woken up by the watchdog timer Anything else would be because of fault or special case int dpslp_chk void extern int countl count2 ReadDSGPR amp read state Read the deep sleep GPR Wireless Bear Tracking Group May1010 Page 164 DeepSleepWakeUpSource amp ptr Check the deep sleep wakup soruce if required ReleaseDeepSleep Release the Deep sleep IO configuration TRISBbits TRISB1 0 configure the IO TRIS and LAT register to output ssignal for LED if read state RegO countl read state Regl count2 countl and count2 represents the state of device before going to deep Sleep while 1 Nop this indicates an error has occurred while in deep sleep if ptr WK_SRC DS_WDT TRUE return 1 deep sleep wakeup source is DSWDT if ptr WK_SRC DS_FLT TRUE return 2 deep sleep wakeup source is Falut in deep sleep
145. ill require an acknowledgment from the router letting the unit know that the data was successfully received This acknowledgment message sent by the router is described as the following preamble ACK start string MAC time CRC ACK end string ACK start string is a unique set of characters that differentiates this message from any other message MAC is the address of the unit receiving the acknowledgement The time of the received GPS data is resent back to the collar unit for extra verification that the ACK message corresponds to the recent message sent CRC is the data needed for bit error checking and correcting ACK end string is the set of bits that lets the router know it has reached the end of the message The transceiver can handle up to 8 bits of a constant one or zero After this the performance starts to degrade To address this issue 8B 10B encoding scheme was chosen packets will be encoding using this scheme It is predicted that at most 150 bytes will be needed for the unit to router data message and at most 25 bytes will be needed for the router to unit acknowledgment message So the total number of bytes needed for data transmission is 175 bytes This is a very high overestimate to prepare for a worst case scenario Referring to the previous equation the number of time slots available can be determined The baud chosen initially is was 300 If 0 5 ms is allocated for the guard periods and 175 bytes are needed for d
146. ine should never be shut off The 3 3V line powers the GPS unit This can be shut off by the PIC when the GPS unit is not in use The 5V line powers Wireless Bear Tracking Group May1010 Page 62 the power amplifier of the transceiver This can also be shut off when the power amplifier is not in use The resistor divider at the bottom steps down the input to 3V so that the PIC s A D can monitor the voltage When the voltage gets below 2 8V which means the input voltage dropped to 5 6V the PIC will detect a low battery This value was chosen based on the ADP3050 datasheet It specifies that the 5V regulator will not supply the required current below a 5 5V input 3 10 Battery The choice for battery had a lot of things to consider It must be able to withstand the harsh environment of the Minnesota woodlands both terrain and climate In addition it must be able to last at least 3 months without a replacement Finally it must be able to deliver the required voltage to power the components 3 10 1 Nickel Metal Hydride NiMH The Nickel Metal Hydride battery is composed of a hydrogen absorbing alloy for the negative electrode Pros High capacity Manyrecharge cycles e Very good performance in high drain devices High self discharge rate Does not function well at low temperatures e Memory effect Wireless Bear Tracking Group May1010 Page 63 3 10 2 Lithium Ion Li ion A lithium ion battery is composed
147. ing to the routing transceiver i The routing device is required to communicate with mobile units when they are within their communication range The routing device is required to communicate with other routing devices ili Routing devices will cooperate to relay readings received from tracking devices to the end user receiver c Pertaining to the end user receiver i The end device is required to receive data from multiple tracking devices The end device is required to receive data from multiple routing devices iii The end device is required to plot location information on a mapping interface Wireless Bear Tracking Group May1010 Page 17 d Miscellaneous i The battery life of the bear transmitter must be 3 months The location must be updated every 15 minutes as a minimum requirement Proper care is taken to secure bear location information 2 2 Non Functional Requirements The non functional requirements for the tracking device are defined below A The physical dimensions of each unit bear transmitter routing device and end device must be appropriate The bear transmitter must be similar to the currently used SPOT Satellite Messengers B The chosen VHF antenna must be appropriately small C devices must be user friendly This could incorporate features like a low battery indication transmission to let the researchers know when it is appropriate to change batteries D The outer shell of the bear tran
148. its LATB1 bits 15 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 14 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 13 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 12 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 11 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 10 for j 0 j lt 2 34 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 9 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 8 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 7 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 6 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 5 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 4 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 3 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbi
149. ke KKK KKK kkkkkkkkkkkkkkkkkkkKkOLD FUNCTIONS void eusartl_rx_int void TXSTAlbits TXEN 0 clear TX enable this clears TX int flag TXSTA2bits TXEN 0 rx RCREG1 if rx gt buff end rx eusart buff return used for Asycronous RX with VHF transciever void eusartVHF rx int void TXSTAlbits TXEN 0 clear TX enable this clears TX int flag TXSTA2bits TXEN 0 int gohere rx RCREG2 rxtt if rx buff end eusart buff return void Find RX Data void Wireless Bear Tracking Group May1010 byte i int j int current data Page 181 char start VHF Count byte VHF RX 6 byte VHF Correct 6 VHF Correct 0 Correct 1 VHF Correct 2 Correct 3 VHF Correct 4 OxAB OxAC OxAD OxAE OxAF VHF Correct 5 0x55 start 0 VHF Count 0 for i eusart buff i rx itt current data 1 if current data 86 start 0 start 1 if start 1 if VHF Count 6 eusart buff trans for 3 0 3 lt 6 if VHF_RX j VHF_Correct j errortt return return else VHF RX VHF Count current data Counttt Wireless Bear Tracking Group May1010 Page 182 Appendix 18 PIC Code interrupts h include datatypes h Define prototypes void eusart2 rx int void void high vector void void low vector void void Find RX Data v
150. l power 33 5 Turn on the transciever and turn the RF switch to mode vhf trx ON switch ctrl TX Delay to allow the transciever to warm up for k 0 k lt 90 k delay for 3 6 ms configure the transciever s registers to TX mode vhf init TX Delay to allow transciever to finish configuring before sending data for k 0 k lt 20 k delay 0 840 ms Sends the packet to the transciever using Eusart 2 VHF send packet packet Makes sure that the last byte has been sent to the transciever while TXSTA2bits TRMT gives time for the transciever to modulate the last packet before powering down for k 0 k lt 8000 k delay 0 840 ms Powers down the 5 volt line and the transciever power 5 OFF vhf trx OFF return Thus procedure sends the formatted packet through the VHF transciever void VHF send packet unsigned char packet int i Sends the preamble for i 0 1 lt 11 1 send eusart2 0xAA send Start Word OxBAD5 send eusart2 0xBA send _eusart2 0xD5 Wireless Bear Tracking Group May1010 Page 172 Send the packet for 1 0 1 lt 19 1 send eusart2 packetti return This procedures gets the VHF data from the I O pin It runs for the length of the packet and is initiated by the interrupt of the rising edge of the VHF data clock void data rx void unsigned char data 0 char
151. l the gps chip to see if it is busy and then send a read message Function gps write loop Params void Returns void Description poll the gps chip to see if it is busy and then send a write message Function get gps data Wireless Bear Tracking Group May1010 Page 207 Params gpsdata Array of UBX NAV PLLH message Returns 1 if message contains valid data at correct accuracy 0 if message timed out and contains no data Description Loops a read to the UBLOX GPS so that the PIC buffer does not fill and waits for a valid UBX NAV PLLH message Also waits to message at correct accuracy and outputs a valid bit unsigned char get gps data unsigned char gpsdata unsigned long accuracy endif Wireless Bear Tracking Group May1010 Page 208 Appendix 26 PIC Code ublox cfg c File ublox CFG c Contains the Configuration messages for the NEO 5 GPS include lt p18 46j11 h gt The PIC used final design include lt i2c h gt include gps_i2c h include eeprom_i2c h include main h include ublox cfg h Function ubx cfg msg off Params void Returns void Description Set the rate that a message is polled to 0 void ubx cfg msg off unsigned char class unsigned char id See page 83 of the Protocol Specification Document char CK A CK B int Inc unsigned char length 11 payload 8 unsigned char message 11 UBX message headers message 0 OxB5 message 1
152. le is determined by update rate It should be set close to 10 kHz The AGC update rate is given by the following equation with a value of AGC CLK DIVIDE of 10 given us the closest value to 10 KHz SEQ 1008kHz 10 08kHz AGC _ Divide 10 6 Write to Register 0 Register 000 0 0 0011 0101 110 1010 0001 0100 0000 Muxout UART Tx Rx TX Integer N Fractional N 27156 Address Regulator Mode No 0 53 Bits Ready 0 Table 9 TX Register 0 value The RF output frequency is calculated by the following equations depending on if RF divide by 2 is set which in our case it is not set to be on For the direct output Fractional _ N 215 PED integer For the RF DIVIDE BY 2 DB18 selected i Fractional RF PFDx0 5x Integer _ N Ana OUT 5 215 Analog Devices An Integer N and Fractional N value of 53 and 27 156 gives us the center frequency of 217 0375 MHz It should be noted that a when the Fractional N is used spurs can appear on the VCO output spectrum at an offset frequency that corresponds to the difference frequency between an integer multiple of the reference frequency and the VCO frequency Wireless Bear Tracking Group May1010 Page 70 Muxout sets the output on the VHF Muxout line Muxout is a digital value and can indicate the different components shown in Table 10 N z 0 0 0 0 1 1 1 1 00 2200
153. le was developed to ensure that the project will be completed on time The completion date of each subtask was based on datelines given to us by the Senior Design class and the estimated amount of time needed for each task Figure 48 shows the schedule for the project Wireless Bear Tracking Group May1010 Page 124 Task Name Duration Start Finish September October November December January February March April May 30 8 6 B 138 208 27110 4 0 1 1 0 1 1111 8 1 121 221 2612 8 2 13 21202124113 nonni 241 1 2 7 BM 422121 2 28 3 7 BM 43 218 28 4 4 amp 118 184 25 572 Problem Definition 8 days Thu 9 24 09 Mon 10 5 09 Problem Definition Completion 8days Thu 9 2409 Mon 10 5 09 Constraint Identification 8days Thu 9 2409 Mon 10 5 09 End User Identification 8days Thu 9 2409 Mon 10 5 08 emm Technology Research and Selection 28 days Thu 9 24 09 11 2 09 Communication and Antenna 8days Thu 9 24 09 10 5 09 GPS and Antenna 8days Thu 9 24 09 Mon 10 5 09 Battery 28 days Thu 9 24 09 11 2 09 Microcontroller Hardware amp Software 8days Thu 9 24 09 Mon 10 5 09 Chassis 28 days Thu 9 24 09 11 2 09 Network Structure 18days Thu 9 24 09 Mon 1049 09 Security 28 days Thu 9 24 09 11 2 09 End Product Design 31 days 10 5 09 Mon 11 16 09 Electri
154. llar Units with VHF Routing Unit eene 19 3 1 2 Collar Units with OrbCom Routing Unit esee 19 3 1 3 Collar Units with Digi 9Xtend Routing Unit eese 20 3 1 4 Other Inappropriate So WOME ebd aM asa tede Sa o a CUM 20 125 5 1 EET T T m 21 24 Network SEPUCUUPE o iod one imas eric n t PAY POR D HAVE VET SUE 22 DM 22 TDMA M 22 323 Detailed TSS i tO 22 Sede VHE liu 29 Jul Frequency 29 mu Transceiver Selectos inro 30 33 3 DOBLES 31 3 4 AU e s oceio nus Den REDE DE RI NEU A dress sristi ssis 42 3 4 1 4 Wavelength Whip vircs Mer t NEM 43 Wireless Bear Tracking Group May1010 Page 3 3 4 2 Ya Wavelength Whip 45 242 Sleeve Dingle Aena 45 3 4 4 Normal Mode Helical yinccccshassescxssrsesathencavaresesdisactuaceniseasasatian
155. ly track the location and movements of black bears for the researchers at the Wildlife Research Institute To improve the efficiency and cost of the research the team is tasked with replacing the current scheme of scanning large forested areas manually with a system that can relay data off site via cell or satellite 2 Key Functional Requirements e Point location every 15 minutes e Weatherproof device e Tough shell that will withstand bear cub jaws e 25 by 10 mile signal coverage 3 State of Implementation team has a working prototype board with all hardware included parts on the board are a PIC microcontroller GPS device external EEPROM memory radio transceiver radio switch power amplifier power supply section At our meeting they had everything confirmed working with the exception of the GPS device The team has also implemented a debugging program on the microcontroller that enables Wireless Bear Tracking Group May1010 Page 129 them to connect a computer to the prototype board and harvest debugging information Also they have fabricated a 1 4th wave antenna 4 System Setup e Open MPLAB e Plug in programmer and connect to it e Verify no errors occurred e Programmer Build All to compile program e Verify no errors occurred e Programmer Program to load program onto microcontroller e Verify no errors occurred e Plug in power supply Plug in USB cable from computer to board e Check that board power an
156. matching network can be seen in Figure 12 As one can see the reflected power at 217 MHz is 40 db Wireless Bear Tracking Group May1010 Page 38 E m MM DT L IND1 78 nH t 6 Term Tem Pu 1 L 38 nH ft Term2 miei a oe 2 Z 50Ohm gt gt Zz159 75 j 53 16 ie DNE 5 li EAM I e CAPEAOpFPIQS 50 Figure 11 RF Output Matching Network Input Reflection Coefficient Forward Transmission dB 5 0 0 10 0 2 15 0 4 20 a 0 0 8 d 25 30 1 0 1 35 14 40 140 160 180 200 220 240 260 280 300 140 160 180 200 220 240 260 280 300 freq MHz freq MHz m1 m2 req 217 0MHz req 217 0MHz 8 5 2 1 4 495 4 dB S 1 1 30 850 Figure 12 RF Output Matching Network Simulation Wireless Bear Tracking Group May1010 Page 39 The RF input of the transceiver was matched to 50 ohms From the application notes the input of the transceiver was modeled at 220 MHz Using the suggested matching network and the approximate values for a matching network at 150 MHz the matching network was able to be tuned to get a match to 50 ohms The matching network L and L5 can be seen in Figure 13 Simulating the circuit see Figure 14 the reflected power was 51 db at 217 MHz with an input impedance of 50 182 4 j0 215 TID HU Ez E E Figure 13 RF Input Matching Network
157. mation from router 1 will successfully be forwarded to router 2 If one collar position is sent to more than one router only one router will send a confirmation ACK to the collar unit Optimization and Initialization Routines e The base router when notified by the user will successfully communicate to all available routers and determine their GPS location Based on this location the router will optimize a networking pattern The pattern must be the most efficient and the base router must locate every other router in the system e When the base router is notified by user it can determine all of the routers that are in use in the field Wireless Bear Tracking Group May1010 Page 105 6 System and Unit Level Test Case Results The following section is the results from the tests recommended in Section 0 Not all test cases were implemented due to time and feasibility constraints 6 1 VHF Spectrum With the transceiver configured to 2FSK we measured the output spectrum using a spectrum analyzer The first time we measured the output spectrum we noticed that we were not getting the power amplification that we should be getting With the transceiver set at a power level of 36 around 0 dBm we were only seeing around 0 dBm We believed that a possible reason for the power amplifier for not working correctly is because there was too much resistance to ground In our PCB design we forgot to add a copper area on the solder mask for the ground
158. milar designs The routers are able to be mounted in desirable locations to easily transmit transmit at increased distances using lower power rates VHF frequencies easily penetrate heavily wooded areas Cons Readily made VHF module is not easily accessible with high power output The network protocol may be difficult to complete Bears may travel outside the range of stationary routers 3 1 2 VHF Collar Units with OrbCom Routing Unit Collar unit will consist of a VHF Transceiver that will allow data to transmit and receive over VHF Frequencies The routing unit will transmit received data to the OrbCom Satellites and the satellites will then transmit to a remote location Pros VHF can transmit at increased distances using lower power rates VHF frequencies easily penetrate heavily wooded areas OrbCom modules are manufactured by Digi Wireless Bear Tracking Group May1010 Page 19 Cons Readily made VHF module is not easily accessible with high power output OrbCom modules have high power requirements Communication to satellite incurs a monthly fee Modules are more expensive and not currently available from Digi Bears may travel outside the range of stationary routers 3 1 3 VHF Collar Units with Digi 9Xtend Routing Unit Collar unit will consist of a VHF transceiver that will allow data to transmit and receive over Frequencies The routing unit will consist of a Digi 9Xtend 900
159. n 10 1 Project Contact Information The following contains the contact information of the client faculty advisor and student team 10 1 1 Client Information Digi International Mark Tekippe Jim Stroner and Jordan Husney 11001 Bren Road East Minnetonka MN 55343 Phone 1 877 912 3444 Email digisd iastate edu 10 1 2 Faculty Advisor Information Dr Ahmed Kamal 319 Durham Hall Ames IA 50011 Phone 515 294 3580 Email kamal iastate edu 10 1 3 Student Team Information Zach Bruce Team Leader 225 N Hyland APT 6 Ames IA 50014 Phone 515 975 7836 Email zbruce iastate edu Blane Chesnut Webmaster 4335 Frederickson CT Ames IA 50010 Phone 515 572 7820 Email bchesnut iastate edu Wireless Bear Tracking Group May1010 Page 126 Chris Donnelly 4335 Frederickson CT Ames IA 50010 Phone 515 572 7820 Email cdonns87 iastate edu John Pritchard Communication Liaison 4700 Mortensen RD Unit 201 Ames IA 50014 Phone 712 389 0381 Email johnp iastate edu Adam Rasmussen 3055 190TH ST Goldfield IA 50542 Phone 515 824 3456 Email adamras iastate edu 10 2 Closing Summary Digi International has presented a problem to our team to find an effective method of tracking the location of bears in Northern Minnesota With current products being expensive we will provide cheaper end product that will provide nearly live location information of bears when possible for researchers wh
160. n because of its kickstart weak signal acquisition technology its compatible I2C interface its package size its low power modes and lower cost due to Digi buying in bulk Other modules were considered including the Trimble Copernicus and Trimble Condor Neither the Copernicus nor the Condor had an I2C interface and both were larger packages than the Ublox The Trimble units did however trump the Ublox module in accuracy update frequency tracking mode power consumption These features were only slightly better than the Ublox and thus expendable Overall the Ublox NEO 5Q was a much more suitable choice 3 6 GPS Antenna Unlike the VHF antenna only one GPS antenna solution is necessary While both bear collars and routers will require GPS antennas the each will be receiving GPS information in similar conditions and restrictions Wireless Bear Tracking Group May1010 Page 52 The antenna will Receive GPS data through thick cover of forestry Appropriate sizing constraint to fit inside device casing e Low cost Durable in conditions seen in Northern Minnesota 3 6 1 GPS Helix Antenna A GPS helix antenna provides the best performance out of all GPS antennas This is especially true when tracking satellites near the horizon when the GPS antenna is facing up into the sky Unfortunately in order to get this type of performance the helix antenna requires a large amount of space to get the correct wavelength for GPS sign
161. ndling interrupts on the PIC18F46J11 4 3 2 4 1 high vector table If a syne word detect interrupt has been enabled external interrupt 1 this function calls the swd function If external interrupt 2 has been enabled VHF RX data clock this function calls data rx function If there is incoming data from the FTDI USB to Serial converter this function calls the esuart2 rx int 4 3 2 4 2 low vector table This function is not implemented yet because no low priority interrupts are set up 4 3 2 4 3 eusart2 rx int This function stores the value that was received in an array called eusart2 buff If the data received exceeds the length of eusart2 buff the rx2 pointer is reset to the beginning of the buffer so that data is overwritten 4 3 2 4 4 high vector When a high priority interrupt occurs the program arrives at this function This function then directs the program counter PC to the high vector table function using assembly code 4 3 2 4 5 low vector When a low priority interrupt occurs the program arrives at this function This function then directs the program counter PC to the low vector table function using assembly code Wireless Bear Tracking Group May1010 Page 93 4 3 2 5 user c This file contains all the functions necessary to run the user interface on a PC Its purpose is to serve as a gateway for the user to access all PIC functionalities 4 3 2 5 1 user ctrl
162. ne if valid data is in the VHF Buff Array These global variables contain the most valid decoded RX data signed long lat 0 lon 0 latitude and longitude unsigned long time 0 Time in ms of week unsigned char status 0 ID 0 Status byte and ID of unit extern byte rx2 extern byte eusart2 buff BUFFSIZE Global structures used in deep sleep library SRC ptr CONTEXT read state functions none declared Wireless Bear Tracking Group May1010 Page 163 desc This function handles deep sleep functionality If the has woken from a deep sleep then counter is incremented Once the counter has completed decisions are made on when to activate the unit void ds handler void int ds handler void int dpslpevent 0 this variable determines what the source of deep sleep wakeup is Check if the device is waking up from deep sleep else it must be a normal power on reset if IsResetFromDeepSleep 0xFF if this is the reset after the deep sleep wakup then do this dpslpevent dpslp chk determine the wakeup source if dpslpevent 1 if wakeup source is from watchdog timer do this if DSGPR1 SCALAR2 amp amp DSGPRO SCALAR1 once the count registers hit a desired point do something Write DSGPR 0x00 0x00 reset the counter data return 3 else return 2
163. nicating with we set the baud rate to 2400 bit size of 8 no parity and one stop bit X PuTTY Configuration Category E E Session Options controlling local serial lines Logging amp Terminal Keyboard Serial line to connect to COMH Bell Features amp Window Speed baud Appearance Behaviour Translation Stop bits Selection Colours Connection Flow control Data Proxy Telnet Rlogin SSH Serial Select a serial line Configure the serial line Data bits Parity Figure 47 Port parameters for communication to PC for Google Map testing 6 4 Specific Absorption Rate Safety The specific absorption rate is a way to measure the amount of energy being absorbed by bodily tissue due to exposure to radio frequency electromagnetic fields It is important for us to take this into account so that we don t injure the bear Since the collar is so close to the bear s head we have to ensure that our outputted power is safe SAR is measured in Watts Kilogram and in our case needs to be evaluated over the mass of the bear s head The FCC requires that all cell phones have a SAR no greater than 1 6W kg Therefore with our system outputting about 1W the bear s head would have to weigh less than 1kg This condition will not be a factor our group will encounter since it is safe to say that the average bears head weighs roughly 5 15kg Also contributing to the safety of our system is the amount of time in which we are transmitting It
164. nna For a block diagram see Figure 5 Wireless Bear Tracking Group May1010 Page 31 GPS Patch Antenna VHF Antenna EEPROM Control Lines RF In RF Out E uae Transceiver 3 rudi 3 3 V A 3 3 V 5V ehe Power Battery Electronics Figure 5 System Block Diagram 3 3 3 0 Transceiver ADF7021 The ADF7021 has been configured to have a bandwidth of 25 kHz a carrier frequency of 217 025 MHz transmit at a data rate of 300 bps and use FSK modulation 3 3 3 3 Microcontroller Interface The data to be transmitted and received by the transceiver is interfaced with the USART of the microcontroller The transceiver s registers are configured by the microcontroller s USART The transceiver has three lines CE SWD and MUXOUT that interface with the general I O of the microcontroller A description of each line can be seen in Table 1 Wireless Bear Tracking Group May1010 Page 32 3 3 V is high and 0 V is low TX VHF SCLK WRITE MK NVHF READ Transceiver s S ADF7021 CE 44 VMHF SWD P S VHF MUXOUT ANT CTLO CTLI RF Switch SKY13270 92LF Figure 6 Interface of Transceiver and RF Switch to Microcontroller Table 1 VHF
165. nna the USB interconnect and the power cables 4 1 1 Printed Circuit Board Layout The PCB layout was done using Cadence Layout Plus Each component on our board has an associated footprint Most of the footprints were included in the standard library but some of the footprints had to be created manually Because of budget constraints we designed a two layer PCB For testing purposes we kept all components on the top side of the PCB and included extra test points and connectors The general strategy for the layout was to keep the VHF and GPS portions as far apart as possible Figure 29 shows the general layout structure of our board Because RF performance greatly depends on the ground plane the PCB board has copper pour everywhere on the board that does not have any components or traces these areas are on both the top and bottom layer of the PCB To try to keep away from breaking up the ground plane with traces we alternated between the top and bottom layer on longer length traces PIC VHF Power GPS Power USB Figure 29 PCB Layout Structure Wireless Bear Tracking Group May1010 Page 65 When starting the layout the most attention was put on the RF portions of GPS section The reason for this is because adding more traces changes the characteristic impedances of the circuit which will result in the parts not being matched to 50 ohms It should be noted that on the VHF portion we h
166. nning of week short int status status variable 2 bytes can use as needed to send flags to receiver struct packet int 28 int send preamble void t TXSTAlbits TXEN 1 enable transmission for int 1 0 1 lt 6 1 send 48 bits of alternating 1 s and 0 s 1 0 10101010 return 1 return 1 for completed preamble Wireless Bear Tracking Group May1010 Page 191 long check sum encode unsigned int counter long encoded 0 encoded encode message counter amp 0 0 encode message counter 4 amp OxOF 5 return encoded Wireless Bear Tracking Group May1010 Page 192 Appendix 21 PIC Code encoding h Number of bytes in packet not including preamble define PACKET SIZE 28 Next largest mulitple of 8 of packet size define PACKET OCT 32 void format packet unsigned char packet signed long latitude signed long longitude unsigned long time unsigned char status unsigned char ID Forms an array of 5 encoded bits which can then be sent to the VHF transciever with a for loop void tx packet shift unsigned char message unsigned char packet signed long rx decode lat unsigned char RX signed long rx decode lon unsigned char RX unsigned long rx decode time unsigned char RX unsigned char rx decode status unsigned char RX unsigned int check sum unsigned char packet int length unsigned char rx decode ID unsigned
167. nt on_off x LATBbits LATB3 on_off return gt Set RF switch to TX mode lt void switch ctrl byte x byte ctrl chk x if ctrl chk 0 If turned off LATEbits LATEO 0 LATEbits LATE1 0 return if ctrl chk 1 put in tx mode LATEbits LATEO 1 LATEbits LATE1 0 return if ctrl chk 2 put in rx mode LATEbits LATEO 0 LATEbits LATE1 1 return else return This procedure is called when a Sync word has been detected by the rising edge of the VHF_SYNC_INT Once a sync word has been detected the pic will retrive the data on the rising edge of the VHF data clock void swd void INTCON3bits INT1IE INTCON3bits INT2IF INTCON3bits INT2IE INTCON3bits INTlIF return 0 disables interrupt 1 0 clears interrupt flag 2 1 enables int 2 VHF RX CLK 0 clears int 1 flag SWD Wireless Bear Tracking Group May1010 Page 169 Configures the board to be in VHF recieve mode and waits until a valid packet is retrived It then checks to see if there are any errors in the recieved packet and if not decodes the data and assigns the data to the corrisponding global varibles When new valid data is available the function returns a 1 unsigned char unsigned char 0 int 0 unsigned int decode chk sum 0 calc chk sum 0 float Avg 10000
168. nt outlined all the data messages and how they would be configured The EEPROM I2C lines were accidentally switched in the original PCB fabrication Jumper lines had to be soldered in order to switch the two lines Future PCBs will be updated to this modification 4 2 5 Power Coupling between the 3 3V line and an unknown source was detected therefore it appeared that the 3 3V line does not fully shut down There is a possibility that devices which use 3 3V line may still be powered even though we prompt it to shut down 4 2 6 Antenna base station antenna was never constructed due to time limitations and material cost However a small whip antenna was constructed for the bear collar This antenna consisted of a RG 58A U coaxial cable terminating at the unit in a 50 O SMA connector The coaxial cable s outer conductor was stripped away for a quarter wave antenna At the radiating frequency of 217 0375 this length was 34 52 cm There was also quarter wave of coax left on the cable This cable helped to match the impedance of the unit and lengthened the antenna for a better fit on the bear collar This construction also leads to a poor interface between the coaxial termination and the radiator This is due to the mismatch between input impedance of the quarter wave antenna and the intrinsic impedance of the coaxial line Some reflection is expected in the S11 parameter of the antenna Wireless Bear Tracking Group May1010
169. ntroller which will then output data to the PC through debugging indicating the PC whether or not the GPS is responsive or the outputted data is valid Hardware e All physical connections are sound e VCC levels are correct e lt 50mV p ripple is observed at VCC pin o I O levels are correct e Unused I O ports are high impedance Functionality Status acknowledgment will be requested by the microcontroller to the GPS module acknowledgment will be expected from the GPS module GPS data request by the microcontroller shall result in an array of pertinent GPS data received by the microcontroller e Bytes will be counted and compared to the predicted set of data as to calculate an accurate time slot pertaining to the network design e GPS status will be checked in times of low power mode to get an accurate low power consumption rate 5 4 Microcontroller Unit Level Test Cases This section describes the testing process that will be undergone once the board has been fabricated The microcontroller will output data to a PC when needed The GPS chip will output data to the microcontroller which will then output data to the PC through debugging indicating the PC whether or not the GPS is responsive or the outputted data is valid Hardware All physical connections are sound VCC levels are correct e I O levels are correct e Unused I O ports are high impedance Wireless Bear Tracking Group May1010 Page 102 Functionality e
170. o use our end product At a unit material cost of 210 and development labor costs of 21 380 we have provided a proof of concept for Digi International that meets their requirements for the project Due to the complexity of this project we strongly recommend that this project be continued for a second phase Wireless Bear Tracking Group May1010 Page 127 Works Cited Advanced Telemetry Systems Series M2500 5 October 2009 17 November 2009 lt http www atstrack com PDFFiles Series_M2500 pdf gt Analog Devices ADF7021 High Performance Narrowband ISM Transceiver August 2009 Analog Devices 29 November 2009 lt http www analog com static imported files data_sheets ADF7021 pdf gt BlueSky Telemetry 30 September 2009 lt http www blueskytelemetry com wildlife_tracking asp gt Burberry A VHF and UHF Antennas London Peter Peregrinus Ltd 1992 Computer Dynamics NEMA 4 and Other NEMA Ratings 2008 29 November 2009 lt http www cdynamics com nema 4 html gt Federal Communications Commission Part 15 Title 47 Telecommunication Part 15 20 February 2009 Federal Communications Commission 29 November 2009 lt http www access gpo gov nara cfr waisidx_08 47cfr15_08 html gt Federal Communications Commission Part 18 Title 47 Telecommunication Part 18 20 February 2009 Federal Communications Commission 29 November 2009 http www access gpo gov nara cfr waisidx 08 47cfr18 08 html
171. objective of Subtask 2 2 is to select the best GPS module and antenna We will approach this task by researching the different modules and antennas available and picking the best GPS module and antenna for this project 8 2 3 Subtask 2 3 Battery The objective of Subtask 2 3 is to select the best battery technology and vendor for our application We will approach this task by researching the different battery technologies and vendors and picking the appropriate battery technology 8 2 4 Subtask 2 4 Microcontroller Hardware amp Software The objective of Subtask 2 4 is to select the microcontroller programming hardware and software and any necessary operating systems needed to run on the microcontroller Depending on the microcontroller selected we will decide if external memory will be needed and if so the appropriate memory will be researched and selected We will also select the appropriate hardware and software needed to program the microcontroller Lastly we will decide if we will need an operating system and if so will pick the best operating system for our project 8 2 5 Subtask 2 5 Chassis The objective of Subtask 2 5 1s to select the appropriate material for the chassis We will research our different options and pick the appropriate material 8 2 6 Subtask 2 6 Network Structure The objective of Subtask 2 6 is to select the appropriate network structure The network structure includes the protocol that will be
172. of a lithium anode and a carbon cathode Pros e Much lighter than other batteries No memory effect High capacity e Very good performance in high drain devices e Very slow self discharge rate Function better than other types at extreme temperatures e Capable of withstanding environmental effects Environmentally friendly More expensive than other types Lower shelf life than other types Dueto high capacity can be hazardous if short circuited 3 10 3 Detailed Design Because environmental conditions are a huge part of the project we decided to go with the Li ion battery because it has much better performance at low temperatures Regardless of the chosen solution there were tradeoffs The higher quality battery will be more expensive overall this will be more beneficial because of the longevity they have over the alternatives Wireless Bear Tracking Group May1010 Page 64 4 Implementation The second semester of the project two PCB s were designed populated and tested Our team narrowed our focus to the hardware development and low level programming leaving high level networking protocols to be implemented in the future The following section defines the implementation of the hardware and software used in the project 4 1 Hardware This section describes the assembly and implementation of the hardware including design changes The basic hardware includes two populated PCB s two VHF antennas one GPS ante
173. of the FSK modulation at 4 8 from each impulse as seen in Figure 38 and also 200 kHz from the center frequency as seen in Figure 39 These images can be cause by using a high number on the fractional n as explained in the transceiver TX register 0 Wireless Bear Tracking Group May1010 Page 106 2 0 00 dBm M1 65535 M1 18 94 dBm AM1 0 01 dB 217 0447 MHz dB div 217 044687 MHz 9 625 2 19 50 10 0 dB RBW 1 00 kHz vBW 100 00 dBm CF 217 0400 MHz Span 50 0 kHz Autoscale CF 217 0400 MHz 9 Span 50 0 kHz Figure 37 Output Spectrum of board A with transceiver set at level 1 power 16 dBm Bitmap M Show Clear Trace2 5 Sample Max 10 Clear 1 18927 gt 10 00 dem MEN 217 0447 MHz dB div 217 044687 MHz 19 50 dBm 10535 gt RBW 1 00 kHz vew 90 00 dBm CF 217 0400 MHz Span 50 0 kHz gt CF 217 0400 MHz Span 50 0 kHz Figure 38 Output Spectrum of board A with transceiver set at level 36 power 0 dBm with span 50 kHz Wireless Bear Tracking Group May1010 Page 107 M2 3 49 dBm 217 056125 MHz SY Li y ano i 60 00 dBm Autoscale CF 217 040 MHz Marker Marker plitud Readout T tude Table 2 Figure 39 MR 0 217 0352 MHz 50 dBm CF 217 0400 MHz n 100 0 kHz 0 Jl
174. oid Define constants define BUFFSIZE 50 Wireless Bear Tracking Group May1010 Page 183 Appendix 19 PIC Code projconfig h Set configuration bits see datasheet for details if defined 18 26711 defined 18F46J11 pragma config WDTEN OFF XINST OFF OSC INTOSC pragma config T1DIG ON LPT1OSC OFF DSWDTOSC INTOSCREF pragma config RTCOSC INTOSCREF DSBOREN ON DSWDTEN ON pragma config DSWDTPS DSPER FCMEN OFF IESO OFF endif Wireless Bear Tracking Group May1010 Page 184 include include include include This procedure takes in a four bit message encoding Appendix 20 PIC Code encoding c lt stdio h gt lt stdlib h gt lt math h gt encoding h long encode message long message long encoded message 0 switch message case case case case case case case case case case case case case case case 0b0000 encoded message break 0b0001 encoded message break 0b0010 encoded message break 0b0011 encoded message break 0b0100 encoded message break 0b0101 encoded message break 0b0110 encoded message break 0b0111 encoded message break 0b1000 encoded message break 0b1001 encoded message break 0b1010 encoded message break 0b1011 encoded message break 0b1100 encoded message break 0b1101 encoded_message break 0b1110 encoded_message 0b11110 0
175. oject We will approach this task by meeting with the client to identify the constraints of the project 8 1 3 Subtask 1 3 End User Identification The objective of Subtask 1 3 is to identify who will be using the end product We will approach this task by meeting with the client to discuss the end use of product 8 2 Task 2 Technology Research and Selection The objective of Task 2 15 to find the best technology to use in the project We will approach this task by separating the different technologies among the team and performing research on different options within that technology After the research has been performed the results will be present to the team as whole At the end of this task we will have the technology selected for the project 8 2 1 Subtask 2 1 Communication and Antenna The objective of Subtask 2 1 is to select the method of communication and corresponding appropriate antenna The method of communication is the technology that we will use to send the GPS data from the bears to the end user i e VHF Satellite ect Along with picking the technology we will decide if we will purchase a module or complete a new hardware design At the end of the task we will know the method of communication between the bears and the end user and whether we are designing the communication hardware or purchasing a completed module Wireless Bear Tracking Group May1010 Page 117 8 2 2 Subtask 2 2 GPS and Antenna The
176. on A Schematic esee 136 Appendix 5 GPS Revision una sa dela 137 Appendix 6 Power SUpply 138 Appendix 7 PCB Layout niena etis saana 139 Appendix 8 Revision B Schema eet REA pL EE CREAN needa deed ead 144 PPI 9 PE P 145 Appendix 10 PIC Code main C 146 Appendix TL PIC Code Main as deett 152 Appendix 12 PIC ode E es 153 Appendix 13 PIC E II MI P M 161 Appendix 14 PIC Code datitvpes Diacono ioni ott dtm suse itd 162 Appendix 15 PIC Code handler cdd 163 Appendix 16 PIC ode Bude todo tibi hu ius MU ne 178 Appendix T7 PIC Code Iierrupis ub 179 Appendix 18 PIC Code aute Uc brane cuc Oct 183 Appendix 19 PIC Code projconfig D uei iens tette ette o etes ta etatis eui 184 Appendix 20 PIC Code ecOH BE eol scrive str i tee Lea c
177. or RX only long reg 6 0 3661 6 long reg 5 5 long reg 11 0 5 5 not inverted sync word 1 error 0x5DAB9B bad5 not inverted 2 errors 0xA2549B 2 errors allowed BAD5 inverted 0xA2545B 1 errors allowed long reg 12 0x13AC packet length of 19 0x5AC packet length of 5 long reg 0 0x49AEA140 Syncronice MoDE digital lock ready 0x99AEA140 0 9 00000 fractional value long reg 4 0x8010F014 k 12 fdev 8 30k 0x8011AA94 k 21 IFBW 25k 0x4011AA94 k221 IFbW 18 5k 0x11AA94 k 21 IFBW 12 5kHz 0x10CA14 k 10 IFBW 12 5k 0x8010CA14 k 10 dis BW 50 long reg_10 0x897043A 4kHz 0x4697043A AFC 35k 0x1897043A 12kHz 0x1497043A 10kHz 0x1097043A AFC at 8k range 0x3297043A AFC at 25 kHz range 0x2097043A 16kHz 0x4B97043A AFC at 37 5kHz 0x3C97043A 30 kHZ 0x3297043A MAX AFC at 25kHZ int k if txrx mode 1 Do TX mode configuration here send gpio reg 1 for k 0 k lt 37 k delay 0 840 ms send gpio reg 3 send gpio reg 0 TX for k 0 k lt 2 k delay for 80 us send gpio reg 2 for k 0 k lt 170 k delay for 3 6 ms if txrx mode 2 Do RX mode configuration here send gpio reg 1 for k 0 k lt 37 k delay 0 840 ms Wireless Bear Tracking Group May1010 Page 158 send gpio reg 3 send gpio reg 6 send gpio reg 5 for k 0 k lt 340 k
178. oup May1010 Page 95 4 3 2 5 15 X print mod This function is used for the gps test function to print location data without any user visual formatting In other words it is the same as print without sending the last 4 3 2 6 Eeprom i2c c The eeprom 12 file includes all the necessary protocols to communicate to the external EEPROM memory 4 3 2 6 1 eeprom i2c init This function initializes the PIC to communicate via the second I2C lines The pins 38 and 39 on the PIC are set as inputs in order for this to function properly This initialization happens at a 100 kHz DC clock which is based off of the 4MHz oscillator clock 4 3 2 6 2 eeprom write byte In the case that only one byte of data needs to be written to the EEPROM this function allows that The inputs must be a single byte as well as which memory block 1 or 0 and the address of memory that the data will be written 4 3 2 6 3 eeprom The EEPROM can be read simply with this function An array or pointer must be passed in as rdptr and this location is where the EEPROM data will be located locally The address and memory block 1 or 0 must also be input The length of string to be read is also necessary 4 3 2 6 4 eeprom ack polling There is no way for the PIC to know when the EEPROM is completed with the writing stages of its operation In order to know when it s done the PIC operates a polling mechanism It waits until the EEPROM respond
179. plane of the power amplifier the only connection to ground is on the underside of the power amplifier To test this we removed the power amplifier from board B and scrapped off the insulation until we got to the top copper ground plane After doing this we put a new power amplifier onto the board which should allow a full connection to the ground pad on the power amplifier With board A having a power amplifier with only plated through hole connections to ground and board B with a full connection to ground we measured the spectrum again of the two boards at three different power levels 1 16 dBm 36 0 dBm and 63 13 dBm Figure 37 Figure 38 Figure 39 and Figure 40 show the screen shots for board A As one can see we never achieved the amplification that we required These screen shots did verify that our boards are modulating using FSK with a frequency deviation of 4 8 kHz We did observe that when we turned the power of the transceiver to maximum level 63 we were seeing the gain dropping tremendously and losing the modulation all together as seen in Figure 40 Contacting the PA manufacturer they believed that the issue was because of not having a good connection to ground and also not having a high Q choke and low resistant inductor on L13 RFMD suggested that we use Coilcraft 1008CS inductor Because of time issues we were not able to see if changing the choke inductor would fix the PA issue We also observed images
180. polling void Wireless Bear Tracking Group May1010 Page 199 Function eeprom write Params address block either 1 or 0 for the page of the memory address the address of the memory to write dataptr Character type pointer to data to write length Number of bytes to write to I2C device Returns void Description write a byte to the EEPROM at the defined address ee void eeprom write unsigned char address block unsigned int address unsigned char dataptr unsigned char length Wireless Bear Tracking Group May1010 Page 200 Appendix 24 PIC Code gps i2c c File gps i2c c Contains i2c funtionaility for the NEo 5 GPS include gps i2c h include eeprom i2c h include ublox cfg h include ublox read h include lt i2c h gt include lt delays h gt Function gps i2c init Params void Returns void Description intialize the I2C for the NEo 5 GPS chip void gps i2c init void LATDbits LATD2 1 Power 3 3V selectable Line DelaylOKTCYx 30 this is about a 300 ms delay After the 3 3V line is on for 300 ms the GPS will look for the eeprom Need to wait this 250 ms for the GPS to be in slave mode T the 3 3V line gets turned off this will need to be waited again TRISCbits TRISC3 TRISCbits TRISCA 1 Set pin 37 as input for I2C to function 1 Set pin 42 as input for I2C to function Set MSSPEnable Bit 5
181. put and Output IF Intermediate Frequency ISM Industrial Scientific and Medical Equipment LEO Low Earth Orbiting used in describing satellite orbits MAC Media Access Control MSK Minimum qshift keying PA Power Amplifier PC Personal Computer PIC Programmable Integrated Circuit Wireless Bear Tracking Group May1010 Page 11 POR Power on Reset RF Radio Frequency RSSI Received signal strength indication RX Receive SAR Specific Absorption Rate SPOT Commercially available personal tracking unit which uses satellites for communication Sync Synchronize TDM Time Division Multiplexing TDMA Time Division Multiple Access Term Description TX Transmit UART Universal asynchronous receiver transmitter UHF Ultra High Frequency the radio frequency range from 300 MHz to 3 GHz URL Uniform Resource Locator VHF Very High Frequency the radio frequency range from 30 MHz to 300 MHz Wireless Bear Tracking Group May1010 Page 12 1 Introduction The following is an overview of the Wireless Bear Tracking Senior Design Project This section includes background on the device the problem statement possible solutions and the product deliverables 1 1 Executive Summary A non profit group from northern Minnesota researches a group of twelve mother bears by tracking their movements using RF transmitting collars worn by the bears These bears are habituated to the
182. r after the fine and coarse filter calibration has been performed These values can be used to manually set the filter calibration without having to run the automatic filter calibration The manual adjustment should only be done when the transceiver has only been powered down for a short period of time The following equation gives the filter adjustment value that can be programmed into register 5 IF FILTER ADJUST FILTER CAL 128 Analog Devices 4 3 2 3 21 VHF Battery RB This function returns the battery voltage as measured at PIN VDD4 The analog to digital conversion ADC needs to be turned on to read the battery value which is performed by writing to register 8 Once the ADC is turned on the battery readback can be performed The following equation is used to calculate the voltage at the battery BATTERY VOLTAGE READBACK Veattery Wireless Bear Tracking Group May1010 Page 92 4 3 2 3 22 Temperture RB This function returns the outside temperature in degree Celsius Just like the battery readback the ADC must be turned on before performing the temperature readback which is performed by writing to register 8 Once the ADC is turned on the temperature readback value can be performed and the temperature can be calculated using the following equation Temp C 40 68 4 TEMP READBACK x 9 32 Analog Devices 4 3 2 4 interrupts c This file contains all functions needed for ha
183. r case the Demod Clk is equal to 2 016 MHz from Register 3 and fae is equal to 4 80 kHz from Register 2 Using the above equation we get a K value of 21 which results in a DISCRIMINATOR BW of 106 To optimize the coefficients of the correlator Product and Rx Invert must be assigned The value of these bits depends on whether K is odd or even The assignment is given in the following table Table 17 Assignment of Correlator K for 2FSK and 3FSK w2 wem re rapean 00 10 sim 00 10 In our case and K 1 2 is also odd This makes Product 1 and RX Invert 0b10 Analog Devices Post Demodulator BW should be set according to the following equation and table 2 xm POST DEMOD _ BW 2 xm foror DEMOD CLK where fcvrorr is the target 3 dB bandwidth in Hz of the post demodulator filter Table 19 Post Demodulator Filter Bandwidth Settings for 2FSK 3FSK 4FSK Modulation Schemes Recelved Post Demodulator Filter Bandwidth Modulation furore Hz 2FSK 0 75 x data rate 3FSK 1 x data rate 4FSK 1 6 x symbol rate 0 8 x data rate Analog Devices In our case the data rate is 300 so is 225 and with Demod clk equal to 2 016 from Register 3 we get a POST DEMOD BW equal to 1 Wireless Bear Tracking Group May1010 Page 78 14 Write to Register 10 Register 0011 0010 100 1011 1000 0010 0001 1 1010 Max AFC KI AFC Scaling AFC Address Range
184. ransmit at a data rate of 50 bps to 32 8 kbps without any external components The transceiver is designed as a narrowband transceiver with programmable bandwidths of 12 5 18 75 and 25 kHz ADF7021 has a receiver sensitivity of 130 dBm at 100 bps with on chip image rejection calibration It also had an on board temperature sensor and battery strength indicator We decided to use the Analog Devices ADF7021 It required fewer external components compared to the Melexis TH7122 It also came with software that helped design the component values of the external circuitry performed simulations of the chip and gave register values to be programmed into the ADF7021 all based on our frequency external oscillator frequency and bandwidth The chip was also the cheapest at 5 76 3 3 3 Detailed Design The following section describes the detailed design for the VHF transceiver This includes diagrams schematics and simulation data 3 3 3 1 Overview The Analog Devices ADF7021 transceiver performs the modulation and demodulation of the data sent from the microcontroller ADF7021 outputs the modulated data at a digitally programmable power range of 16 dBm to 13 dBm to an external power amplifier SPA 1118 made by RFMD This power amplifier has fixed gain of 17 2 db and an output power at 146 compression of 29 5 dBm SPA 1118 outputs to RF switch SKY13270 92LF made by Skyworks which connects the RF output and RF input to a single 50 ohm ante
185. reduces cost and complication It further saves design time in that it communicates via UART which is very easy to implement in the controller chosen PIC18F46J11 The integrated patch antenna can be bypassed if required the EM 408 has an MMCX connector for an optional external antenna 7 5 General Design Recommendations Few changes were needed based off of flaws found in the previous revision First the SDA and SCL communication lines were switched on the EEPROM to PIC interface and are corrected in this design Secondly the RX and TX lines need to be switched to be able to use USARTI Also a different crystal oscillator was used for the VHF transceiver to account for the required frequency tolerance Wireless Bear Tracking Group May1010 Page 115 8 Statement of Work The project will be broken down into seven tasks Table 27 and every member of the team will contribute to complete these tasks Table 27 Tasks to be accomplished Task 1 Problem Definition Subtask 1 1 Problem Definition Completion Subtask 1 2 Constraint Identification Subtask 1 3 End User Identification Task 2 Technology Research and Selection Subtask 2 1 Communication and Antenna Subtask 2 2 GPS and Antenna Subtask 2 3 Battery Subtask 2 4 Microcontroller Hardware amp Software Subtask 2 5 Chassis Subtask 2 6 Network Structure Subtask 2 7 Security Task 3 End Product Design Subtask 3 1 Electrical Hardware S
186. registers and puts the PIC back into deep sleep 4 3 2 3 4 send eusart1 This function sends the user inputted integer value via USART 1 It checks to make sure that the buffer it not full before sending the next byte of data 4 3 2 3 5 send esuart2 This function sends the user inputted integer value via USART 2 It checks to make sure that the buffer it not full before sending the next byte of data 4 3 2 3 6 send gpio This procedure writes the specific register value to the transceiver It takes in the register value and shifts each bit into an array These bits are then fed from most significant bit to least to the transceiver The procedure sets up the bit s value on the VHFW line and then toggles the SCLK to generate the required clock The procedure performs this for all 32 bits After the last bit is read by the transceiver the VHF SLE is set high for a period to latch the data into the transceiver and then finally set low again For timing requirements on this procedure Section 3 3 3 3 contains more details Wireless Bear Tracking Group May1010 Page 89 4 3 2 3 7 eusart test This function tests the eusart port by calling the send eusart function to send specific values from 0x00 to 0x03 4 3 2 3 8 sleep count This function increments the counter variables count and count2 These variables are set at zero when a pure POR has occurred When counter passes 255 it resets to zero and increments
187. rom the RX data signed long get lon void return lon Returns the current time from the RX data unsigned long get time void return time Returns the current Status byte from the RX data unsigned char get status void return status Returns the current ID from the RX data unsigned char get return ID This procedure retrives GPS data formats the data and sends it wirelessly via the transciever void TX void int k unsigned char gpsdata 36 Will store the UBX NAV POSLLH message unsigned char packet array 19 will contain the encoded packet to send unsigned char packet packet array pointer to packet array signed long longitude signed long latitude unsigned long msTOW Store the milisecond Time of Week Gets the GPS data to send get gps data gpsdata 20000 will receive a GPS data with accuracy of 20 m Wireless Bear Tracking Group May1010 Page 171 longitude ubx navpllh get longitude gpsdata latitude ubx navpllh get latitude gpsdata msTOW navpllh get msTOW gpsdata Encodes the GPS data into a packet format packet packet 0 190 0848 Ox37CFOF1C 0x240C8400 Ox0F 0x01 format packet packet latitude longitude msTOW 0 0 0 01 Sets up the Ports on the PIC for VHF Transmission eusart2VHF remap TX syc eusart2 init TX Power on the 3 3V and 5V rai
188. rs attempt to send the acknowledgement simultaneously the signals could interfere with each other and be ignored by the bear After all bears have transmitted their location the routers will then transmit locations back to the home computer in the order from the furthest router towards the closest router Once again the distances will be calculated according to the GPS locations This will be the method used to get the locations of all the bears back to the home router 3 3 VHF Transceiver The chosen design will make use of a VHF Transceiver The following section describes the frequency selection transceiver selection and detailed design for the selected transceiver 3 3 1 Frequency Selection In order to achieve better distances in the dense woods frequencies in the VHF spectrum were considered in both the unlicensed and licensed bands These bands were the unlicensed band at 174 to 216 MHz ISM band at 40 MHz and the licensed band at 216 to 220 MHz Wireless Bear Tracking Group May1010 Page 29 The first band we considered was unlicensed band at 174 to 216 MHz This band allowed a bandwidth of 200 KHz and maximum field strength of emissions of 1500 microvolts meter at 3 meters The field strength was calculated to limit our transmission power to 32 dBm of power to the antenna For our application this was not enough power Federal Communications Commission Part 15 The second band we considered was the ISM band at 4
189. s Bear Tracking Group May1010 Page 22 3 2 3 1 General Network Skeleton Consider the case where four routers are placed in predetermined spots within the area of concern Also consider several units scattered throughout this area but within range of at least one router This could be described in Figure 2 below 4a 8 4b 1 Home lt 4 8 4c 2 3a gt 3 2a 8 amp 8 8 5 2b 2c 8 Figure 2 Network Example In the case above there are nine users present in the network of four routers the first being home base It is required that location data from each bear is routed to home base every 10 to 15 minutes units and routers are transmitting and receiving the same frequency so a fitting modulation scheme needs to be decided upon 3 2 32 General TDM TDM Time Division Multiplexing is a great choice for this application The idea is that a data stream is divided into separate frames in the time domain Multiple users then share a piece of that frame a time slot Each user is allowed to transmit and receive for the amount of time allotted in the time slot For example consider Figure 3 below The top section of this figure displays a data stream of which is divided into separate frames Each frame is then divided into different time slots in this case four Thus there are four possible users that can talk to a host device at very specific times Wireless Bear Tracking Group May1010 Page 23
190. s function initializes all GPIO pins to be either digital or analog inputs or outputs 2 3 2 2 7 vhf init This procedure configures the transceiver to be in either transmit or receive mode The procedure contains the register values needed to be written to the transceiver For more information on the registers values see Section ADF 7021 Register Configuration4 1 3 The register values are passed to the procedure send gpio which writes the values to the transceiver s registers The for loops are added to make the required delays as defined in Section 4 1 3 4 3 2 3 handler c This file contains functions that perform any type of data handling This involves the deep sleep functionality sending eusart data sending data via I O ports and other functions for peripheral testing purposes Wireless Bear Tracking Group May1010 Page 88 4 3 2 3 1 ds handler This function is called to decide whether or not the power on reset POR was pure or if it was from a deep sleep wake 4 3 2 3 2 dpslp chk This function is called to determine whether or not the power on reset POR was pure or if it was from a deep sleep wake 4 3 2 3 3 go to sleep This function is called if a wake from a deep sleep has occurred but the wake is not at the beginning of a TDMA network frame When this function is called it increments a counter by calling the sleep count function It then writes this counter information to the deep sleep save
191. s that could have been chosen such as assembly but using this would complicate the programs needed to be written far too greatly 3 8 Chassis The chassis took into account a number of parameters in choosing the optimal solution The chassis needs to be able to withstand the rugged environment i e shock and vibe waterproof temperature as well as the bears themselves We were informed that the bear cubs tend to chew on the collars during the hibernation time Therefore we needed an encapsulation that was small enough but could still endure the effects of its use as well as one that could contain circuitry without having any effect on the circuit s performance 3 8 1 Commercial Cases These plastic cases are meant to hold cell phones wallets and cameras Their focus is for personal use for protection of the users valuables Pros e Waterproof e Crushproof e Buoyant Case Environmentally friendly Cheap Dimensions and layout aren t customizable Simple latch for closing Wireless Bear Tracking Group May1010 Page 55 3 8 2 Industrial Cases These polycarbonate cases meet industry standards and are meant for housing electronics Pros e Waterproof e Buoyant case Customizable shape and layout e Premade cases Environmentally friendly Cheap Cons Unknown lead time if customized design 3 8 3 Detailed Design The industrial cases were chosen because of their required fulfillment of industry s
192. s to an address and then the unit is available for a second write 4 3 2 6 5 eeprom write This function is formatted very similar to the read function It takes all the same parameters but this time the dataptr has values to be written to the EEPROM instead of available space to be written to Wireless Bear Tracking Group May1010 Page 96 4 3 27 gps_i2c c This file contains all the initialization and basic functionality for the first pair of ID2C lines on the PIC which communicate to the GPS 2 3 2 7 1 gps i2c init This function initializes the UBLOX 12 lines to 31 25 kHz if the internal oscillator is properly tuned to 4 MHz The I2C lines communicate on pins 37 and 42 of the PIC and these are both configured as inputs Another important bit to set is the Slew Rate Control Bit which allows the signals to be properly recognized by the GPS The UBLOX initially configures itself as master to an external EEPROM This function waits 300ms in order for this sequence to complete before initialization 4 3 2 7 2 gps This function will read the message stream on the UBLOX chip The chip does not always have data available and this may not print any values in the rdptr This function also returns the length of the data that was read which is important when looping for data as this function is often used 4 3 2 7 3 gps write This function is used to write a message to the UBLOX Messages are not often written
193. s to the transceiver one for configuring the transceiver s registers and the other for sending and receiving data wirelessly To configure the transceiver s registers we generated our own procedure that produced the desired sequence as explained in Section 3 3 3 3 The procedure is explained in more detail in the transceiver software Section 4 3 2 3 6 To send data we used the PIC s USART It should be noted that the USART lines for TX and RX to the PIC and ADF7021 were switched around in using USART 1 PIC PIN 44 should be connected to TXRXCLK Pin 35 PIC PIN 1 should be connected to TXRXDATA Pin 34 of the transceiver On the current revision A we worked around this issue by using USART 2 which can be programmed to PIC Pin 1 and 44 and this issue has been switched in the revised schematic Using USART 2 we configured the PIC s USART to act as the slave The transceiver provides the clock to output the data on the rising edge More details on this can be seen in Section 4 3 2 2 and 4 3 2 3 In receive mode we do not use the PIC s USART Instead we use the transceiver s sync word functionality The transceiver is programmed to look for a specific start sequence of bits which in our case is OXSDAB Once the transceiver sees this sequence of bits it sets the VHF SWD INT high which tells the PIC to start to read the bits on the rising edge of the transceiver s outputted clock Once the whole packet is read in the VHF SWD INT is set low until the next
194. s used to detect the rising edge of the receive clock of the transceiver 232173 eusart2 init This function initializes all registers required to communicate serial data asynchronously over the EUSART2 module Wireless Bear Tracking Group May1010 Page 87 4 3 2 2 4 syc eusart2 init This procedure initializes the synchronous transmission and reception In transmission mode the synchronous USART 2 is used to send the data The USART is set up in synchronous and slave mode and disables transmission interrupts The transceiver acts as the master and outputs the clock to shift the data out In receive mode the USART is not used Instead the receive procedure uses interrupts Two interrupts are needed one for the sync word detection and the other for the rising edge of the transceiver clock External interrupt and 2 are tied to the sync word detection and transceiver data clock respectively Thus in receive mode this procedure sets up external interrupt and 2 to be activated on the rising edge External interrupt 1 is the only interrupt that is activated right away because we do not need to start clocking in data until the start character has been detected Lastly the procedure calls global var init which initializes the received data array and count variables to zero 4 3 2 2 5 osc init This function initializes all registers required for the PIC s internal oscillator to oscillate properly 4 3 2 2 6 io init Thi
195. send val send val gt gt 1 Set enable pin LATBbits LATB2 0 Writes to the register by setting the write port and the generating the clock LATBbits LATB1 bits 31 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 30 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 29 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 28 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 27 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 26 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 25 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 24 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 23 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 22 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 21 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 20 for j 0 j lt 2 j LATDbits
196. smitter must be very durable 2 3 Technology Requirements A The chosen wireless technology must have the ability to penetrate dense forestry B The electrical components must be able to handle extreme environments approximately 40 C 70 C C The chosen design frequency and output power must be harmless to bears and humans Wireless Bear Tracking Group May1010 Page 18 3 Approach and Product Design Results The following describes the approach that will be taken to achieve the wireless bear tracking solution This section describes the overall system and network structure as well as the individual components that will be included in the system The considered approaches are all evaluated and the finalized approach is described in detail 3 1 0verall Bear Tracking Structure Having a functioning structure for communication is critical We considered a number of solutions including VHF satellite cellular and Digimesh From these choices we narrowed down our options based on pros and cons of each alternative 3 1 1 VHF Collar Units with VHF Routing Unit Collar unit will consist of a VHF transceiver that will allow data to transmit and receive over VHF Frequencies to the nearest routing unit The routing unit will use a predetermined and programming network protocol to send information to collars and to other routers until the information is received at the remote research station Pros Router and Collar will be very si
197. ssaget it 7 lt lt 3 Encodes the status and ID and adds to packet packet j messageti 1 lt lt 5 j packet j message i 3 lt lt 7 j packet j return message i 1 gt gt 3 message i 2 lt lt 2 3 gt gt 1 Performs check sum the encoded packet for TX mode unsigned int check sum unsigned char packet int length Check Sum Fields unsigned int CK A 0 int i 0 sums up all the decimal values of the shifted packet except for the last data value because it only has 4 bits in it so it needs masks Wireless Bear Tracking Group May1010 Page 188 for i 0 i lt length 1 CK A packet i masks the last byte to get only the last four digits CK CK packetti amp OxOF Only use 10 bits in the check sum CK A CK A amp Ox3FF return CK A Decodes the latitude data from the encoded shifted packet signed long rx decode lat unsigned char RX long lati lat2 lat3 lat4 lat5 lat6 lat7 lat8 lat 0 latl decode message RX amp 0 1 lat2 decode message RX gt gt 5 RX 1 lt lt 3 amp 0x1F lt lt 4 lat3 decode message RX 1 gt gt 2 amp Ox1F lt lt 8 lat4 decode message RX 1 gt gt 7 RX 2 lt lt 1 amp 0x1F lt lt 12 lat5 decode message RX 2 gt gt 4
198. t accuracy unsigned char message unsigned accuracy accuracy accuracy accuracy accuracy accuracy accuracy long accuracy 0 0000 amp message 29 lt lt 8 accuracy accuracy accuracy accuracy accuracy accuracy return accuracy 0x0000FF amp message 28 lt lt 8 0 0000 amp message 27 lt lt 8 0x0000FF amp message 26 Wireless Bear Tracking Group May1010 Page 217 Appendix 29 PIC Code ublox read h ifndef UBLOX READ H_ define UBLOX READ H_ Function valid ubx msg Params message Character type array of the UBX message read from the NEO 5 Returns 1 Message is a valid UBX Message 0 Message is not a valid UBX Message Description Read the first two bytes and confirm UBX Message Function ubx msg length Params message Character type array of the UBX message read from the NEO 5 Returns Unsigned int Description return the length of the message including the header and checksum fields Function ubx msg class Params message Character type array of the UBX message read from the NEO 5 Returns Unsigned char of Class Description Returns the class of the message Function ubx msg id Params message Character type array of the UBX message read from the NEO 5 Returns Unsigned char of ID Description Returns the ID of the message Function ubx navpllh get latitude Params message Character type array UBX NAV PLLH message Ret
199. t is important to provide documentation on the device in terms of a user manual and a technical specification document so that it is easily modified and usable Suggestions for improving the unit as well as preliminary plans for the next generation are all important deliverables Wireless Bear Tracking Group May1010 Page 16 2 Design Requirements The following describes the requirements defined for the project design Any solution must meet the requirements laid out in this section 2 1 Functional Requirements The VHF UHF terrestrial communication solution will involve transmitters placed on the bears to communicate with routers posted in selected spots within the area of concern GPS location information would be received by the modules on the collars and then transmitted to the onsite routers The routers would then relay the bears GPS location information to an onsite base station This information would then be processed accordingly by the researchers See Figure 1 Bear VHF UHF VHF UHF Base Station VHF UHF Router A Router B Transmitter Figure 1 VHF UHF Solution The functional requirements pertaining to a VHF UHF solution are defined below A Local VHF UHF Solution a Pertaining to the transmitter on the bear i The tracking device is required to receive GPS data via GPS satellites ii The tracking device is required to transmit data to routers via local VHF UHF transmitters stationed within defined area b Pertain
200. tandards The cases meet National Electrical Manufacturers Association NEMA standards 1 2 4 4x 12 and 13 These standards are shown in Table 4 Standard Description NEMA 1 Enclosures constructed for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment and to provide a degree of protection against falling dirt NEMA 2 Same as NEMA 1 including protection against dripping and light splashing of liquids NEMA 4 Enclosures constructed for either indoor or outdoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment to provide a degree of protection against falling dirt rain sleet snow windblown dust splashing water and hose directed water and that will be undamaged by the external formation of ice on the enclosure NEMA 4X Same as NEMA 4 including protection against corrosion NEMA 12 Enclosures constructed without knockouts for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment to provide a degree of protection against falling dirt against circulating dust lint fibers and flyings and against dripping and light splashing of liquids NEMA 13 Enclosures constructed for indoor use to provide a degree of protection to personnel against incidental contact with the enclosed equipment to provide a degree of protec
201. tate Figure 8 below from the datasheet shows the timing for readback Wireless Bear Tracking Group May1010 Page 34 wn o gt gt 9 T esl am amp OB 2 t 1 pog le 14 Figure 8 Timing Diagram for Readback Analog Devices Data to be transmitted is sent on TX and data received is received on RX These lines are asynchronous and will be sent at the bit rate set in the transceiver 3 3 3 4 Programming after Initial Power Up After VHF CE is brought high the registers in the transceiver must be reprogrammed Figure 9 and Figure 10 are the suggested programming sequences for transmitting and receiving from the ADF7021 datasheet Wireless Bear Tracking Group May1010 Page 35 XTAL POWER DOWN REF ERE NCE CE LOW CE HIGH WAIT 10ys 1ms REGULATOR POWER UP TYPICAL XTAL SETTLING WRITE TO REGISTER 1 TURNS ON VCO WAIT 0 7ms TYPICAL VCO SETTLING WRITE TO REGISTER 3 TURNS ON Tx Rx CLOCKS WRITE TO REGISTER 0 TURNS ON PLL WAIT 40ys TYPICAL PLL SETTLING WRITE TO REGISTER 2 TURNS WAIT FOR PA TO RAMP UP ONLY IF PA RAMP ENABLED WAIT FOR Tx LATENCY NUMBER BITS REFER TO TABLE 12 I WRITE TO REGISTER 2 TURNS OFF i WAIT FOR PA TO RAMP DOWN 1 I Figure 9 Transmit sequence after power up Analog Devices 2009 Wireless Bear Tracking Group May1010 Page
202. tennas The motor will allow for more possibilities of mechanical failure The motor will consume battery e The rotation of the antenna may possibly miss signals when they are sent Wireless Bear Tracking Group May1010 Page 47 3 4 6 Helical Antenna Array Instead of a rotating antenna several directional antennas can be set up with their antennas connected in parallel One simple directional antenna is a helical antenna Above the helical antenna was used in normal mode as a possible collar antenna Here the helical antenna will be used in axial mode because the diameter of the loops shown as variable D in Figure 18 will be much larger than the wave length of the transmitted signal C IID Figure 18 Helical Antenna Burberry The radiation pattern for each instance of the helical antenna will overlap so that in all directions horizontally there is a high gain pattern Typical gains for Axial Mode Helical antennas are between 10 and 15 dB compared to an isotopic radiator The radiation pattern is very narrow which will contribute to several antennas necessary for the array Pros e Antenna is relatively inexpensive and can be hand made e Has a very high gain up to 15 dB Impedance can be matched using discrete components e The antenna has a very narrow aperture and will require several antennae to build an effective array e The axial mode antenna are difficult to support especially in harsh climate Wireless Bear Tra
203. tery detection Several voltage regulators were considered for the power supply circuitry This subsection will describe the different types and models considered as well as the chosen solution 3 9 1 Linear Regulators Initially linear regulators were considered Specifically the LM317 was the linear regulator of choice This regulator provided the required current allowed for a large input voltage range was adjustable for a large output voltage range and was readily available It was unfortunately very inefficient and thus dismissed as an option Figure 22 LM317 Wireless Bear Tracking Group May1010 Page 57 3 9 2 Switching Regulators In researching more efficient regulators it was found that switching regulators should be used in our design Several regulators of this type were considered The first considered was the LM2717 This device was very suitable as its current output was beyond the requirement it had a dual output such that 3 3V and 5V could be obtained on the same chip and separate shutdown pins were available Unfortunately the input voltage needed to meet our current output was not sufficient Figure 23 LM2717 The second considered was the MA X863 This device also gave very high output current capabilities a dual output of 3 3V and 5V were available on the same chip separate shutdown pins were available and even a low battery detect pin was provided The input voltage needed to meet our
204. the Calibration is performed This could be set manually if desired IR portion is used for image rejection calibration which can be used with an external microcontroller to calibrate the image rejection We are currently are not calibrating 8 Wait at least 5 2 ms for IF calibration 9 Write to Register 11 Sync Word Detect 0000 0000 0101 1101 1010 1011 01 01 1011 Sync byte Sequence OxSDAB Matching Sync Byte Address but must be loaded least Tolerance Accept Length 16 11 significant bit to most significant 1 Error bits bit and inverted Table 19 RX Register 11 value The transceiver can be set to look for a certain sequence of bits and when this sequence is found the SWD is asserted high In our application we use the sync word to act as a start sequence that tells us that a valid transmission is coming We chose a start sequence of OXBADS However in when the PIC uses synchronous transmission it sends the least significant bit first at 8 bits at a time Because of this the transceiver must look for OxSDAB The transceiver also allows for a matching tolerance which is the number of errors in the sync word that are allowed in the detection Wireless Bear Tracking Group May1010 Page 76 10 Write to Register 12 SWD Threshold Setup Register 0001 0011 10 10 1100 Data packet length SWD Mode SWD Lock threshold mode Address 19 Pin High after next Lock threshold 12 s
205. the best choices were a 22uH inductor and a 100uF tantalum capacitor with 75mQ ESR Using these values the new Vripple is E m EV The inductor chosen must be able to handle the proper current draw 3 3V supply is estimated to draw between 250mA and 300mA For worst case scenario we will assume the regulator draws 120mA According to the ADP3050 datasheet the inductor must be able to handle 20 more than the peak switching current The calculations for this are shown below 1 Isw pk Iout max 2 Iripple 120mA 0 5 x 337 5mA 0 28875A 1 20 x Isw pk 1 20 x 0 28875 0 3465A where Isw pk is the peak swing current Iout max is the expected maximum output current and Iripple is the output ripple current After much research it was found that a 22uH inductor with 350mA current rating was sufficient The values for the passive components calculated above will be used for both 3 3V regulators 3 9 3 3 Switching Inductor and Output Capacitor Choice for PA The power amplifier requires an input of 5V without a specified maximum ripple voltage For consistency a maximum ripple voltage of 25mVPP Thus the switching regulator must be designed to meet these conditions The equations used previously are repeated and the MATLAB plot was redone using the output voltage of 5V The code and output for this 1s shown below in Figure 28 Wireless Bear Tracking Group May1010 Page 61
206. the transceiver 2 Wait around 1 1 ms This required delayed is necessary to allow the power regulators to power up VHF MUXOUT will be asserted high when the regulators are ready Wireless Bear Tracking Group May1010 Page 67 3 Write to Register 1 VCO Oscillator Register 1 00 0011 0 1 11 00 1 0 0000 001 0001 External VCO VCO Bias RF VCO CP XTAL Bias XOSC XTAL Clock out R Address VCO Center given divide Enable Current 20uA higher Enable Doubler divide Counter bits Yes Nominal from by 2 ON Set to current faster Yes using off Table 9 off 2 mA power up external NO Set to 1 0 75mA crystal Table 7 TX Register 1 value The phase frequency detector PFD is given by the following formula based on whether the RF divide by 2 is on or off If XTAL DOUBLER 0 PED XTAL R_ COUNTER If XTAL_DOUBLER 1 PED em 2 R_ COUNTER Analog Devices Maximizing the PFD frequency reduces the N value which will reduce the noise multiplied at a rate of 20logio N The PFD frequency is used in the carrier frequency and frequency modulation Analog software ADIsimSRD also gave a lot of the values needed based on our configuration ADIsimSRD also suggested a PDF frequency of 4 032 MHz The charge pump current was set to the highest value to have the fastest charge rate 4 Wait at least 0 7 ms 5 Write to Register 3 Transmit Receive Clock Register 00 1010 0010 1000 1101 0010
207. thick forest better than the higher frequencies We are using the SPOT unit as an acceptable size and weight Digi will provide funding and technical advice and it is assumed that this will continue throughout the project Wireless Bear Tracking Group May1010 Page 15 After the completion of this project we do not expect to have much direct contact with the researchers We have to make the assumption that if the unit is well documented and somewhat simple to use the researchers will be able to properly use the unit without supervision and guidance 1 7 Limitations Our basic limitations on this project are time and experience We have only one year to develop this prototype and a project such as this could easily be a several year project of the group members are Electrical Engineers and our current knowledge base of networking and programming is not as strong as required by this project We will need to spend extra time researching these technologies A second limitation has to do with access to the area It is a nine hour drive to the forest and we do not have the ability to test our equipment in a similar environment We will have to estimate and rely on different calculations to determine the best technology 1 8 Expected End Product and Other Deliverables At the end of the project the researchers expect three collar tracking units and two router units to be prototyped and ready to field test Along with the prototypes i
208. tile Sleeping period postscalars for the watchdog timer have only certain set of sleep periods so the sleep counter increments those periods gt This function sends eusartl data lt void send eusartl int datatx int send val send val datatx TXSTAlbits TXEN 1 enable transmission TXREG1 send val Send byte return gt This function sends eusart2 data void send 2 datatx int send val send val datatx while PIR3bits TX2IF makes sure shift register is empty before sending new infomation TXREG2 send val Send byte return this procedure writes to the VHF register void send gpio long reg val int i j k b long send val reg val Define bits byte bits ARRAYLEN for b 0 b lt 32 b bits b send_val amp 0x01 send val send val gt gt 1 Set enable pin LATBbits LATB2 0 Send bits to i o LATBbits LATB1 bits 31 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LATB1 bits 30 for j 0 j lt 2 344 LATDbits LATD7 j for k 0 k lt 37 k Data Bit Wireless Bear Tracking Group May1010 Page 166 LATBbits LATB1 bits 29 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit LATBbits LAT
209. tion against falling dirt against circulating dust lint fibers and flyings and against the spraying splashing and seepage of water oil and non corrosive coolants Table 4 Nema Case Standards Computer Dynamics These cases can also be equipped with heavy duty waterproof prevention options This will ensure no intrusion of water Also because they are composed of polycarbonate they have a very high tolerance to impact and wear over time Wireless Bear Tracking Group May1010 Page 56 3 9 Power Supply Circuitry The power supply section will take the power from the battery and allow it to be readily available to all components in the system at the power allowances necessary Table 5 shows the components in the unit and the power requirements for each of these components Component Maximum Required Current Required Voltage PIC microcontroller 15 mA 3 3 V UBLOX GPS Module 80 mA 3 3 V Analog Devices 23 5 mA 3 3 V Transceiver Power Amplifier 330 mA 5V Table 5 Power Requirements Essentially after much research it was decided that four AA batteries would serve as the input to three high efficiency buck converters These step down regulators would be used to provide the 5V and two 3 3V power lines A tap directly on the 6V output would be stepped down with a voltage divider whose output would serve as the input to an A D converter on the PIC18F46J11 This voltage tap would provide for low bat
210. tion maintenance Duties include checking if all peripherals are not faulty and void maintenance void return void tx test void int k eusart2VHF remap TX eusart2 init TX power 33 power 5 ON vhf trx ON switch ctrl TX for k 0 k lt 90 k delay for 3 6 ms vhf init TX for k 0 k lt 20 k delay 0 840 ms send eusart2 0xAA send eusart2 0xAA send eusart2 0xAA send eusart2 0xAA send eusart2 0xAA send eusart2 0xAA send eusart2 0xAA send eusart2 0xBA send eusart2 0xD5 send eusart2 0xAC send eusart2 0xAD send eusart2 0xAE send eusart2 0xAF send eusart2 0x55 while TXSTA2bits TRMT for k 0 lt 8000 k delay 0 840 ms power 5 OFF vhf trx OFF return desc This function serves to perform maintenance at final wake also setting the required startup registers for the peripherals Wireless Bear Tracking Group May1010 Page 150 void rx test void int k int 0 3 1 float temp 0 long Silicon Rev float AFC 10 float Avg AFC 0 Syc eusart2VHF remap eusart2 init RX power 33 ON power 5 OFF vhf trx ON Switch ctrl RX for k 0 k lt 90 k delay for 3 6 ms vhf init RX while 1 Find RX AFC i RB Avg AFC Avg AFC AFC i 2 j i if
211. ts LATB1 bits 2 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 k Data Bit Wireless Bear Tracking Group May1010 Page 167 LATBbits LATB1 bits 1 for j 0 j lt 2 j LATDbits LATD7 j for k 0 k lt 37 Data Bit LATBbits LATB1 bits 0 for j 0 j lt 2 J LATDbits LATD7 jifor k 0 k lt 37 Data Bit release enable LATBbits LATB2 1 for k 0 k lt 37 k LATBbits LATB2 0 Turn off data and clock pins LATBbits LATB1 0 LATDbits LATD7 0 return gt Send and Receive 0x00 0 03 lt void eusart test void int send val for send val 0x00 send val lt 0x03 send 1 send eusartl send val Send send val over EUSART return gt Sleep Count Incrementer void sleep count void extern int countl count2 extract counter data from deep sleep save registers countl DSGPRO Low count register count2 DSGPR1 High count register The two count registers will make a 16 bit counter in the following code increment the counters if countl OxFF countli t if countl gt OxFF count2 countl 0x00 return void power 33 byte x int off x LATDbits LATD2 on off return Wireless Bear Tracking Group May1010 Page 168 void power 5 byte x int on off x LATCbits LATC5 on_off return void vhf_trx byte x i
212. ts the Current Filter Gain from the data LNA gain data gt gt 9 amp 0x03 gets the LNA gain from data Gets the Gain Mode Correction based on the LNA Gain and I Gain Filter Gain The data is from the tranciever datasheet on page 32 if LNA gain 0x02 amp amp I gain 0 02 gain correction 0 else if LNA gain 0x01 amp amp I gain 0 02 Wireless Bear Tracking Group May1010 Page 176 gain correction 24 else if LNA gain 0x01 amp amp I gain 0 01 gain correction 38 else if LNA gain 0x01 amp amp I gain 0 00 gain correction 58 else if LNA gain 0x00 amp amp I gain 0 00 gain correction 86 RSSI Formula in dBm is 130 Readback RSSI Gain Correction 0 5 return 130 gain correction RSSI 0 5 Reads back the Filter Calibration of the transciever This is used for manual filter adjust Filter Adjust FILTER CAL READBACK 128 IF Filter Adjust can be read to R5 DB 14 19 long Filter Cal RB void long reg val 0x187 long data 0 data data amp OxFF masks the data so only first eight bits are used return data 128 Reads back the Battery Voltage which is read from VDD4 float VHF Battery RB void long reg val 0x157 long data 0 send 0 1708 enables ADC data VHF read back reg val data data amp masks the data so only first seven bits are used send 0 1608
213. ubtask 3 2 Embedded Programming Subtask 3 3 Software Design Subtask 3 4 Chassis Task 4 End Product Prototype Development Subtask 4 1 Acquire Materials for Prototypes Subtask 4 2 Assemble Prototypes Task 5 End Product Testing Subtask 5 1 Test Planning Subtask 5 2 Test Development Subtask 5 3 Test Implementation Task 6 Presentations Subtask 6 1 Project Plan Subtask 6 2 Design Review Subtask 6 3 Client Subtask 6 4 Industry Review Panel Task 7 Product Documentation Subtask 7 1 Project Plan Development Subtask 7 2 Design Document Development Subtask 7 3 Project Poster Subtask 7 4 Project Final Report Development Subtask 7 5 Weekly Status Email Wireless Bear Tracking Group May1010 Page 116 8 1 Task 1 Problem Definition The objective of Task 1 is to clearly define the problem constraints and end users that the client has presented We will meet with the client to fully understand the problem and ask for clarification when needed At the end of this task we will clearly understand the client s expectations of the project 8 1 1 Subtask 1 1 Problem Definition Completion The objective of Subtask 1 1 is to clearly define the problem the client has presented We will approach this task by meeting with the client and performing research on current wildlife tracking methods 8 1 2 Subtask 1 2 Constraint Identification The objective of Subtask 1 2 is to define the constraints of the pr
214. um of board B with modification and transceiver output power level of 63 13 m 110 Figure 44 Antenna A S11 Parameters iuo diee oto eb enne 111 Figure 45 Antenna 2 S11 Parameters 112 Figure 46 Port parameters for communication to PC for Google Map testing 113 Figur for MC 125 Fig re 48 Top 139 Fig re 49 Bottom Copp rt Lael oues ido ebenso raton tura quits 140 liste led qm 140 Fig r 51 Bottom SOAR 141 Fig re 52 Top Silk Sereen ESENE aia 141 Ligure 53 Silk cra etu un Pad dunes 142 Figur 54 PES M RN 143 Wireless Bear Tracking Group May1010 Page 9 Appendix 1 Operations Manual Done by Joe 0 040000 129 Appendix 2 Operations Manual Done by Jamin Hitchcock esse 132 Appendix 3 and Power Amplifier Revision A Schematic 2 222422121 135 Appendix 2 Microcontroller Revisi
215. urns Signed Long of lattitude Description Returns lattitude of the message lowest seven digits are decimal Returns in 1 7 Wireless Bear Tracking Group May1010 Page 218 Function ubx navpllh get longitude Params message Character type array UBX NAV PLLH message Returns Signed Long of longitude Description Returns longitude of the message lowest seven digits are decimal Returns in 1 7 Function ubx navpllh get msTOW Params message Character type array UBX NAV PLLH message Returns unsigned Long of ms time of week Description Returns the unsigned long of ms so far in the week Function ubx navpllh get accuracy Params message Character type array UBX NAV PLLH message Returns unsigned Long accuracy measurement in mm Description Returns the unsigned long of estimated accuracy measurement in milimeters unsigned long ubx navpllh get accuracy unsigned char message Wireless Bear Tracking Group May1010 Page 219
216. ved and Gg are the gain of the transmitting and receiving antennas Note that this is not in dB but is a direct ratio of the max directional gain of the antenna is the wavelength of the transmitted signal and is the distance between the two antennas In this system due to the poor gain of the antenna on the bear collar the antenna gain for the router antenna will have to be much higher The following describes several different antenna types and then the detailed design will incorporate the final selection of collar and router antenna 3 4 1 14 Wavelength Whip Antenna The 4 wavelength whip antenna would enter the unit under the neck of the bear and wrap around the bear s neck stitched into the collar At the defined frequency of 217 MHz the length of this antenna would be approximately 12 07 inches This would wrap around the bear s neck stitched into the collar and slightly protrude near the top of the collar The monopole antenna would require a large ground plane which the small unit may not be able to provide The large ground plane is the reference for the signals that will be transmitted to the antenna It will be necessary in this situation to have an entire ground plane on the printed circuit board The antenna would be connected directly to the transceiver This antenna would not require any transmission line but the entire wire connecting the antenna to the transceiver will act as part of the antenna Other signals
217. ync word for data after next sync word packet length for data packet length Table 20 RX Register 12 value The lock threshold locks the automatic frequency correction AFC and automatic gain correction We set this lock to last as long as the data packet length 11 Write to Register 0 Register 010 0 1 0011 0101 110 1010 0001 0100 0000 Muxout UART Tx Rx RX Integer N Fractional N 27156 Address Digital Mode 1 53 Bits Lock Detect 0 Table 21 RX Register 0 value Digital Lock Detect indicates when the PLL has locked When the phase error on five consecutive cycles is less than 15 ns lock detect is set high and remains high until a 25 ns phase error is detected at the PFD See Section 4 1 3 1 Transmit Mode for details 12 Wait 40 us 13 Write to Register 4 Demod Register 10 00 0000 0001 000110 1010 10 1 001 0100 Post Demod Discriminator Rx Product DeMod Address BW BW 1 BW 106 Invert Scheme 25kHz Invert 2FSK Data Correlator Table 22 RX Register 4 value Demodulation Scheme is set to 2FSK Correlator which is used for 2FSK and has better performance than the Linear Demodulator for 2FSK Wireless Bear Tracking Group May1010 Page 77 The Discriminator BW is given from the following equations 3 DEMODCLKxK Round mw 400 10 L J v 3 DISCRIMINATOR BW Analog Devices ou
218. yte tx packet shift message packet performs the check sum on the shifted message counter check sum packet 17 encodes the check sum and puts it in the message message 28 encode message counter amp 0x0F Wireless Bear Tracking Group May1010 Page 187 encode message counter gt gt 4 amp OxOF counter gt gt 8 amp 0x03 29 message 30 packet 17 packet 17 message 28 lt lt 4 packet 18 message 28 gt gt 4 message 29 lt lt 1 message 30 lt lt 6 return Performs the compression of the data to be sent It takes advantage of the fact that encoded 4b 5b data has 3 unused bits and thus shifts the next encoded 4b 5b data into the previous 3 unused bits void tx packet shift unsigned char message unsigned char packet int 0 int 31 0 Shifts the data in the encoded 4b 5b data to prevent wasting bits that are not used in the 4b 5b scheme for i20 i lt 24 i i 8 packet j messageti message i 1 lt lt 5 j packettj messagetit3 lt lt 7 j packettj j packett j messagetit 4 gt gt 4 messagetit5 lt lt 1 messaget it 6 lt lt 6 j packettj j 1 gt gt 3 messagetit 2 lt lt 2 3 gt gt 1 4 lt lt 4 messaget i 6 gt gt 2 me

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