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STR4500 User Manual

1. cccseeceeeeeeeeeeeeeeeeeaeeees 51 Logging NMEA Messages from a reC IVel ccccseeeeeeeeeeeeeeees 54 RTCM Differential Correction Me SS Q S ccccseeeeeeeneeeeeees ote Software Reference Choosing and using scenarios 5r OV CNVIGW oiran a a ae 57 Choosing a SCOMANO tee vucasheenicsssadevtacbne teaadueantudaundsbiadesbeuecswasetex 57 Files IMa SCOMAM On a E ea Vneewcen Gok 59 Software Reference Remote Command Settings 61 Remote command SYNHAX cccceseceseseeeseseeeseseeseeeeseeeeeneeeeens 62 Commands from a file ce eccceeececcseeeeecaeeeeeeeeeeeesaeeeeeeeaeeeesaaeeees 64 Commands via an IEEE 488 interface cccceeceeeseeeeeeeeeeees 65 Commands via a TCP IP socket interface cccccsseeeeeeeeeees 66 Commands via an RS 232 interface cceeccccseeeeeeeseeeeeeneeeees 67 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA TABLE OF APPENDICES A My GPS receiver won t navigate Hints and Tips 69 A 1 General Considerations ccccccecceceececeeececeeeeseeeeeseeeeceeeeseees 69 A 2 SignalLevelS errar E allt as ada achat 71 A 3 My Receiver navigates but not very accurately ccee 72 A 3 1 Factors affecting receiver accuracy cccccseeeceeeeeeeeeaeeeeeeeaees 72 B Synchronisation to other test EQUIDMENTL ccceeeeeeeeeeeee ees 75
2. DGPO0603AAA 1 07 5 4 3 4 Hardware Settings Interrogates and displays information from the connected STR4500 Hardware Options and Settings Ioj x Serial Number f Configuration cTR4500 Serial Number OO01 Firmware issue 00 37 Motherboard issue 0x00 Timer FPGA issue 0x84 EPLD issue A DSP board issue O01 Signal Generator FPGA issue Ox Modulator FPGA issue Ox External Trigger Disabled 1FFS Out iPPs Tees Reference Frequency External Frequency 10 MH Internal Locked Unlocked External ii L OC Cancel As well as displaying current settings several may be changed External frequency references external triggering trigger modes the 1PPS signal and all aspects of synchronisation to other systems is discussed more fully in Appendix B External Trigger If the system is to be started from an external event set the required mode 40 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA Options are 1 Disabled No external trigger 2 Immediate In this mode the internal clock is stopped and restarts immediately on the rising edge of a signal applied to the External Trigger connector The scenario will start coincident with the rising edge of the External Trigger signal 3 Delayed The internal clock is not halted The scenario starts on the next rising edge of the internal 1PPS clock following a rising edge of the signal applied to the External Trigger connector
3. If FIXED mode is specified then Ly Base Signal Level and is constant throughout the scenario lf MODELLED mode is specified then Ly Base Signal Level when the GPS receiver is on the earth s surface and the GPS satellite is on the horizon A on the following diagram During the scenario Ly is constantly modified proportionally to the distance between the satellite and receiver If the receiver remains stationary Ly will be a maximum when the satellite is directly overhead B on the following diagram STR4500 User Manual 89 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 The signal level may be further modified in two ways a A Transmitter TX antenna pattern may be applied to the GPS satellite Typically a GPS satellite TX antenna will have minimum loss in the direction of the centre of the earth and maximum loss in the opposite direction If TX antenna modelling is specified during scenario generation the signal level is modified according to the TX antenna attenuation in the direction of the satellite receiver RX path ory This option is only available to users of SPIRENT s SimGEN For VMS or SIMGEN software packages see Appendix D Unless specifically stated supplied scenarios on the CD ROM do NOT apply a TX antenna pattern 90 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA b A Receiver antenna pattern may be applied to the receiver At scenario g
4. Simulation_state ARMED X RUNNING RES pmmP y TRIG IN IMMEDIATE MODE When using the Immediate Trigger mode the timing requirements for the rising edge of TRIG IN with respect to EXT REF IN are the same as for the 1PPS IN input i e 10ns setup 20ns hold However there is a delay of six 10MHz clock cycles after the STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO0603AAA trigger is recognised before the simulation starts This is shown below XT_REF_IN_ 10MHz thold 20 ns min tsetup 10ns min TRIG_IN Pn Internal_1O0MHz_clock 1PPS_OUT Simulation_ state ARMED RUNNING B 4 TRIG IN DELAYED MODE In delayed trigger mode to start on a defined 1PPS event the rising edge of TRIG IN must occur at least 1 1 milliseconds before the 1PPS OUT rising edge STR4500 User Manual 77 Spirent Communications Limited 2002 1 07 DGPOO603AAA C REQUESTING SCENARIOS FROM THE SPIRENT WEB SITE C 1 REQUESTING A SCENARIO Customers with warranty or support agreements may request and specify custom scenarios from the SPIRENT website http www positioningtechnology co uk From the home page menu click on Service and Support then select STR4500 Multi Channel GPS from the product selector Once on the STR4500 page read the on line text and then click on the click here hyperlink Now select either the Terrestrial Scenario Request form or the Spacecra
5. cccceccecceccesceeeeeeeeeeeeeeeeeseeeueeaueaeuaneees 2 5 1 5 Date Time WINdKOW c cccccccccccceccecseeceeeseeeeeeeeueeeeueeeeuueeeeuuueeueess 28 5 1 6 THEY StatUS Bal sectisnte cee ittacccsecliccecpatinn a 29 5 2 OTM VV INGOWS esascs aa seaptece ede aaa aeia Ni 29 5 2 1 Position Details WINKOW c ccccccccccecceceeceeeeeeeeceeeeeeeueeaeeaenees 29 5 2 2 Antenna Pattern WINdOW ccccccccccceceeceeseeseeeeeeeeeeeeeeeeeseeeeeeees 30 5 2 3 Satellite Data WINGOWS cccccc cece cececseeeeeeseeseeeeueeeeeseeeeeeeneueeees 31 5 2 4 Power Level Adjustment WINdGOW cccccseeeeseeeeeaeeeeeeeeeesees 33 9 2 9 Ramp Window Pseudorange modification ccccccseeeeeeeeees 34 STR4500 User Manual 3 Spirent Communications Limited 2002 DGPOO603AAA 1 07 5 3 5 4 5 4 1 5 4 2 5 4 3 5 4 4 5 4 5 5 4 6 6 6 1 6 2 6 3 6 4 6 5 T 7 1 2 7 3 8 8 1 8 2 8 3 8 4 8 5 The Tool Bar ControlScan es 37 METU D 2 aaa E E eee metre yer keer ere 38 FILE WSU eaen cael eet iatie tie a aha iar satoeetia 38 VIEW MENU igna a antewseetinearauntebaa ace 38 OPTIONS MENU Acrarasianen ae e aE ea 39 TOOESMON U ann ae a a a ne ante 44 WINDOW MentUsicsgsnne ne ides sacsiaaseueoeaioeek 45 FELEM AU e a asta stenuec ed eaeastaueteee 46 Software Reference NMEA and RTCM Messages 49 MrOdUCION saaana aaa a Aa 49 RS 232 POM SEWING S snai eana a aaea aa 50 Simulation data NMEA MeSSag6
6. Note this is an example only read CONTENTS HTM on your disk for accurate data An example scenarioname TXT file is shown below Scenario name Description Start time Aircraft over pole To exercise receiver at medium dynamics over the pole 12 02 2000 12200200 0920 Ny 35 0 Ezy 100M 100 m s Default settings Actual for week 24 None Start Position Maximum velocity Constellation Almanacs Errors STR4500 User Manual Spirent Communications Limited 2002 58 1 07 DGPOO603AAA 7 3 FILES INA SCENARIO Each scenario directory contains several files which are briefly described here The user may inspect substitute or modify some of the files as shown in the following table File type gt Description Ss Scenarioname S IM_ Binary This is the file that is selected Seoneroname Sm Brey io runie simulation o V1 VEH Binary Contains vehicle type wen ee imaan o e V1A1 ANT Binary Contains antenna 1 position MANT LEM end oreiatonon verce 1 m e a antenna 1 on vehicle 1 V1A1PAT1 CSV Contains antenna pattern for comma antenna 1 on vehicle 1 separated See Appendix E for details variable V1A1S1 SIG Binary Data about the composite ba Signal data for each of the 12 V1A1S1C1 CHA to Binary V1A1S1CC CHA channels on the STR4500 RTCM SC104 Differential corrections data Only present if scenario originally compiled with RTCM option o aa Scenarioname TXT ASCII v x De
7. SPIRENT DGP00603AAA Communications STR4500 GPS SBAS SIMULATOR WITH SimPLEX SOFTWARE USER MANUAL PROPRIETARY INFORMATION THE INFORMATION CONTAINED IN THIS DOCUMENT IS THE PROPERTY OF SPIRENT COMMUNICATIONS SW LIMITED EXCEPT AS SPECIFICALLY AUTHORISED IN WRITING BY SPIRENT COMMUNICATIONS SW LIMITED THE HOLDER OF THIS DOCUMENT SHALL KEEP ALL INFORMATION CONTAINED HEREIN CONFIDENTIAL AND SHALL PROTECT SAME IN WHOLE OR IN PART FROM DISCLOSURE AND DISSEMINATION TO ALL THIRD PARTIES TO THE SAME DEGREE IT PROTECTS ITS OWN CONFIDENTIAL INFORMATION COPYRIGHT SPIRENT COMMUNICATIONS SW LIMITED 2000 2002 Microsoft MS Windows98 Windows2000 and WindowsXP are registered trademarks of Microsoft Corporation Issue 1 07 Oct 2002 STR4500 User Manual Spirent Communications Limited 2002 DGPOO0603AAA 1 07 RECORD OF ISSUE 1 01 May 2000 Changes to Section J4 and addition of Record of Issue Table Changes to Section B 1 to add details of STR4500 Scenarios button and acknowledgement process 1 02 May 2000 Changes to Section J 1 to reflect updates in the Product Specification document MS2980 Issue 3 00 Change Ref DCR37 May 2000 Formatting changes and corrections to tables Sept 2000 Windows2000 new Zip and FTP utilities Dec 2000 Changes to Logo DCR0053 Software now named SimPLEX remote control Jan 2002 facilities added DCRO083 New antenna pattern edit new NMEA messages DCR0O138 RTCM corrections no
8. This option is only available when RTCM messages are included in the selected scenario The receiver under test must be RTCM capable to use these messages See the receiver documentation to set up the receiver to use them This option must be selected before the simulation is started From the Menu Bar select Options gt RTCM Differential Corrections RICH Differential Corrections This simulation contains a file RTCM DIF containing diferential correction mesages which may be sent to your recelver via an RS 232 por Forto use com x W Enable Also write ASCI formated correction messages to fallowing tile ic Program Files GS345 TR4500 rtcem_scen rtcm_data tet Browse S W Enable Help Cancel Check the Port to use Enable option then select the port required If you wish to write the messages to a file then check the Also write ASCII formatted correction messages Enable option and select the name and location for this file The default is a file named RTCM_ DATA TXT stored in the currently selected scenario folder To view the messages as they are transmitted go to the Menu Bar and select View gt RTCM Window This will display the following window STR4500 User Manual 55 Spirent Communications Limited 2002 DGPO0603AAA RTCM Differential Correction Messages ST ID ST ID ST ID ST ID ST ID ST ID ST ID ST ID ST ID ST ID ST ID ST ID NOTES 1 HLT 0 ZCNT 1
9. 2 TXT 512 bytes 18 05 00 15 58 F 4500_2HOURS_DURATION_V2 ZIP 149MB 18 05 00 16 16 2 4500_3_CHANGE OVERS_V2 TXT 512 bytes 15 06 00 13 51 4500_3_CHANGE OVERS_V2 ZIP 399KB 15 06 00 13 52 os 4500_4_CHANGE OVERS_V10 TXT 512 bytes 15 06 00 13 27 NETSCAPE y 4500_4_CHANGE OVERS_V10 ZIP 398KB 15 06 0013 28 COMMAND gt NOOP 4 E SYS SYSDEVICE GPSSIM 4500_DATA 2 Objects selected Selected 400 KB j 192 200 1 248 E Local Browseri Select the ZIP and TXT files for the chosen scenario and drag and drop them to the required location on the PC Typically C Program files Spirent Communications SimPLEX Scenarios When completed click on the Disconnect icon and close the SmartFTP application You may now unzip the scenario as described in Appendix C 2 88 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA E ANTENNA PATTERN EDITOR EA INTRODUCTION For those users wishing to make use of the supplied antenna pattern editor the following description is given as an aid to understanding the calculation of signal levels for the STR4500 When a scenario is generated either a FIXED or MODELLED signal level may be specified Additionally a BASE SIGNAL LEVEL may be specified with respect to the minimum GPS signal level defined in STANAG 4294 default is OdB Let the result of these choices be called the UNMODIFIED SIGNAL LEVEL or Ly
10. 7 SOFTWARE REFERENCE CHOOSING AND USING SCENARIOS 7 1 OVERVIEW The SimPLEX software installation procedure installs a recommended directory folder structure for scenarios unless the user chooses to override this and example scenarios called Example_Scenario1 and Example_Scenario2 The default installation places each scenario in its own sub folder under the Scenarios folder for example C Program Files Spirent Communications SimPLEX Scenarios example_scenario1 example_scenario1 sim By default the complete set of scenarios supplied on the installation CD are also installed on the user s hard disk under the same directory structure To add or delete scenarios from the hard disk run the install program on the CD and select the Modify option This allows groups of scenarios to be selected for installation or removal 7 2 CHOOSING A SCENARIO Your system has been pre loaded with a large number of scenarios Each scenario is located in its own subdirectory folder under the Scenarios directory as described above Each scenario specific directory will have the same name as the scenario and will contain amongst other files one named scenarioname TXT This file describes the main features of the scenario Use Windows Explorer to view the available scenarios then any text file editor e g Notepad to read the scenarioname TXT file for further information on the scenario The Scenario directory also includes an HTML fil
11. The DOP prefix indicates the DOP type specified during scenario generation For guidance a number of 1 to 2 5 is good 9 is poor See Section F 5 for further details The RAMP buttons allow pseudorange errors to be applied to a selected satellite This is described in Section 5 2 5 Satellites with a currently active ramp are denoted by an R adjacent to the satellite number on the sky plot Similarly multipath signals are denoted by an M adjacent to the satellite number Double clicking on the Sky Plot window displays the Satellite Data window which shows satellite and signal data in tabular form see Section 5 2 2 The satellite data screen may also be selected via the Menu Bar View gt Satellite Data Window or via the Tool Bar 26 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 5 1 4 POWER LEVELS WINDOW The Power Levels window shows the signal level currently being simulated on each channel wm Power Levels dB paged A ae har ta PRN 2 5 7 6 9J 10 13 17 23 26 The number above each bar below for negative values is the signal level in dB with respect to a level of 130dBm the minimum received GPS signal level as quoted in ICD GPS 200 This value is truncated to an integer for display The number at the bottom of the screen below each column is the PRN of the satellite on that channel Satellites which are switched OFF by the user show OFF rather than a signal l
12. 00 00 7 Hours Minutes Seconds Duration 1Hr30 Contact Numbers USA Military Govt Start Latitude foo deg foo mins foo secs North gt Sales 714 692 6565 Start Longitude ooo deg foo mins oo secs East USA Military Govt 4 Start Height S rt z 2 m 847 817 7098 WGS 84 am pests Static Start Period 10 minutes USA Commercial Sales 44 1803 546325 Vehicle Motion CAR static gt USA Commercial iis s Support Clock Noise None 44 1803 546333 Tropospheric Delay Modeled 7 Europe Mid East Sales Ionospheric Delay Modeled 44 1803 546325 Europe Mid East Almanac 24 perfect orbits Support ENERO ease SBAS Signals None gt TCM Differentia Asia Sales i or Ben jal Yes 7 44 1803 546303 orrecuons p EE RE S RTCM Ref Station oo foo j foo North gt 44 1805 546333 Latitude Offset 00 deg 00 mins 00__secs North RTCM Ref Station jooo oo foo fi Longitude Offset 000 idegj 00 minsj00 secs East Send Scenario to Spirent Communications You must enter your company details e mail address and the serial number of your STR4500 hardware Then fill in each option to describe the scenario you require On line help is available for each field 80 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA When finished select Send Scenario to Spirent Communications If the form is successfully submitted then an acknowledgement scree
13. 2 Ll L2 Delay Fixed Modelled Tropospheric Delay Disabled Stanag BD2 RTCA96 RTCA98 plus parameter if Stanag model selected ITonospheric model Table of Alpha and Beta params for what is modelled and what is transmitted at upload L and Upload z Remember that any of the above being present in a scenario may result in a receiver performing at less than its expected accuracy STR4500 User Manual 73 Spirent Communications Limited 2002 DGPO0603AAA 1 07 A 3 1 1 Summary For absolute receiver accuracy testing select a scenario with none of the deliberate errors described above applied You should also attempt to choose a scenario with tropospheric and ionospheric models that match the models in the receiver under test You may check what errors and models are applied by examining the NAV_SAT TXT file for the selected scenario 14 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA B SYNCHRONISATION TO OTHER TEST EQUIPMENT B 1 INTRODUCTION some users may wish to incorporate GPS simulation into a larger system test environment Often this will require precise time synchronisation between the STR4500 and other items of test equipment and a requirement that the GPS simulation and other aspects of the overall system start at precisely the same point in time The STR4500 incorporates a number of input and output signal ports which can be used in various ways to synchronise time between the simu
14. 2002 DGPOO0603AAA 1 07 5 4 3 6 Message Reporting Selects the message types displayed in the Messages window and written to the log file MESSAGE _LOG TXT in the user s current directory Display the Messages window by clicking on the Messages icon on the Tool Bar or from the Menu Bar selection View gt Message Window Message Options X selectthe message levels you wish to display and log to file MESSAGE LOG Level Display Log to File Debug E E Into Warning Error Fatal The user may select the categories of message displayed It is recommended that Error and Fatal categories should always be selected In addition any BITE messages from the STR4500 hardware are always displayed and logged These are displayed as message type Hardware Fatal messages will produce a pop up warning box and termination of a simulation if running 5 4 3 7 Remote Command Settings This option allows the selection running and modification of scenarios from a user program on the same PC or on a different computer via various interfaces or from a command file See section 8 for details 42 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 5 4 3 8 RS 232 Port Settings Sets parameters of the PC s RS 232 ports for use by the RTCM and NMEA options Described in Section 6 2 5 4 3 9 RTCM Differential Corrections Sends RTCM SC104 format differential correction messages via an RS 232 por
15. B 1 WATFOGUIC MOM 2s ese css hesaxes tacdeeSaleneeageed eecbarise a a a el 15 B 2 Required input signal timing ccccscccsseceseeeeeseseeseseeeseneeens 76 B 2 1 TPPSIT pst eth ilnas antec a iae tach bees 76 B 3 TRig in immediate mode ccccseeccceeeceeeeecseeeeceeeeeseneeeseaees 176 B 4 Trig in delayed MOE ccccseeeceeeeeeeeeeeseeeeeeeeeeceeeesseeeeseneeess 7 C Requesting scenarios from the SPIRENT web site 79 C 1 FREGUESTING ASCON AMO soseri etehetateaiale 19 C 2 UNZIPPING a scenario file 1 0 cece cee eeceeeeeeeeeeceeeeesaeeeeseeeesees 81 D Building Scenarios USING THE SimGEN For VMS and SimGEN SOPTWARE SU UT BS riie a aa sas 83 D 1 ITER GUC TON aise a cticetose tic oa a aa eee 83 D 2 Downloading THE SCENARIO ccccceeccccsseeeeeseeseeeeaeeeeeeaeeees 84 D 2 1 mo FITC EEIN POP VM Giriya e a 84 D 2 2 Downloading using SmartFTP cccceccceeeseeeeeeseeeeeeeaeeeeeaaeeees 86 E Antenna Pattern editor ccccccceecccseeceeeeceseesaeeeceeeeeeeseaeesaeeess 89 E 1 WIWOGUCH OM 62 2 5 aches tae aa aaa aoe 89 E 2 Modifying replacing the RX antenna Attenuation pattern 93 ES Viewing Modifying the RX Antenna Gain Pattern 0 95 F MISCELLANEOUS GPS INFORMATION ccccccseeeeeeeeeeees 97 F 1 Week number Z count and GPS time 0 eeceee eee eeeeeeeees 97 F 2 Tropospheric and lonospheric delay ccccscc
16. ENVIRONMENTAL oasis ed pee ia eee ute ete cee neecd ate aaaiatet eect 116 Contacting SPIRENT ficdssus cock aranhada ainan aaa casasedessiaseess 117 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 1 INTRODUCTION Thank you for purchasing an STR4500 GPS SBAS Simulator and SimPLEX software from SPIRENT world leaders in the field of Satellite Navigation Systems Simulation The Global Positioning System GPS is based upon a constellation of earth orbiting satellites supporting world wide precise positioning navigation and timing for both terrestrial and earth orbiting vehicles Satellite Based Augmentation Systems SBAS provide enhanced accuracy availability and integrity for GPS users in the civil community via one or more geosynchronous satellites The Wide Area Augmentation system WAAS is a system planned for the continental United States Similar compatible systems are also planned for Europe EGNOS and the Far East MSAS The STR4500 fully supports both standard GPS and SBAS The STR4500 is a standalone 12 channel L1 C A code GPS Simulator It has been designed as precision test equipment for evaluating GPS SBAS receivers in the areas of design verification production test comparative evaluation statistical data generation through extended and repeated tests and incoming product test The SimPLEX software is supplied with a variety of pre prepared simulations on CD ROM with a wide range of sce
17. External frequency If you intend to connect an external frequency standard to the rear panel EXT REF IN then set the STR4500 for the appropriate frequency External signals of 1 5 and 10MHz are valid You must press the Apply button to immediately activate any changes made The STR4500 is interrogated continuously while this screen is displayed so if an external reference frequency is detected the Reference Frequency changes from Internal to External When connecting an external reference it will take around 30 seconds to lock during this time the Unlocked indicator is active Note that you cannot run a simulation while the reference frequency is Unlocked and an error will occur if the reference frequency becomes unlocked during a simulation The 1PPS Out field is used to select the signal on the rear panel connector of the same name Options available are 1PPS Continuously outputs 1Hz pulses with the rising edge of each pulse coincident with the simulated GPS 1 second epoch Gated As above but the signal is disabled before a run so that the first rising edge coincides with simulation time O start of run Rising A single rising edge occurs at simulation time O start of run High Sets signal permanently high Low Sets signal permanently low 5 4 3 5 Logged Receiver Data Allows NMEA format messages from a receiver to be displayed and logged to a file Described in Section 6 4 STR4500 User Manual 41 Spirent Communications Limited
18. attenuator the S N ratio for the rear panel is artificially high For this reason the above arrangement they may not yield an identical receiver performance A It is strongly recommended that a DC block is inserted between the receiver input and any external attenuation as a safety measure In this case an option is to make or purchase an antenna for example a simple dipole which is attached to the STR4500 RF output The antenna is held in close proximity to the receiver Due to the unknown coupling of this arrangement it may be necessary to either use an external amplifier on the STR4500 front panel output or to use the rear panel MON CAL high level output to provide sufficient signal level If you wish to construct a suitable dipole then for the GPS L1 frequency of 1575 42MHz each arm should be approximately 4 8 cm long A design for a simple dipole follows STR4500 User Manual 15 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 S ARM OF DIPOI tp FATN IV ke J LU A Note that in this mode you are radiating a GPS signal although at a low level which could conceivably interfere with local GPS users At the same time your receiver is susceptible to signals from real GPS satellites This set up should therefore only be used in an RF screened environment 16 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 4 RUNNING YOUR FIRST SIMULATION It is assumed that the PC and STR4500 are conn
19. correctly acquires those that are simulated If the sliders reach 20dB and false locking is still occurring then signal level must be decreased by adding attenuation If however satellites are still not tracked with the signal levels increased then try increasing the signal level further in stages In both options it is good practice to try and arrange for the SimPLEX power slider range to cover the receiver s dynamic power range To STR4500 User Manual 71 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 ensure this it may be necessary to revisit the attenuator values in option 2 or add external attenuation in option 1 Note your connection setup and signal levels for future use with that receiver type A 3 MY RECEIVER NAVIGATES BUT NOT VERY ACCURATELY A 3 1 FACTORS AFFECTING RECEIVER ACCURACY There may be several reasons for this apart from the possibility of a receiver malfunction It is assumed the signal levels are adequate and that there are sufficient satellites simulated to give a reasonable DOP Examine the NAV_SAT TXT file in the current scenario folder to determine the following Relevant extracts from the NAV_SAT TXT file are shown for each point e Has deliberate signal degradation been applied to the scenario Diverge Ephemeris Disabled Enabled e Is ISCN Intentional Satellite Clock Noise enabled This will introduce a time varying error of up to 100 metres or more This option simulates the Se
20. displays the current antenna attenuation pattern in both Cartesian and polar formats see Appendix E for further details on antenna patterns 30 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 9 2 3 SATELLITE DATA WINDOWS The Satellite Data window displays satellite signal data for each channel in tabular form Satellite Data Chan Type SVID PRN Elev Tropo lono Pseudorange PRRate Power Delay m Delay m m m s dB GPS 39 6 0 0 0 0 22537630 279 96 13 00 GPS 15 4 0 0 0 0 240259725 542 36 13 00 GPS 16 3 0 0 0 0 24097494 5 414 03 13 00 GPS 47 0 0 0 0 252531 46 4 615 00 13 00 GPS 37 8 0 0 0 0 21933891 6 476 11 13 00 GPS 23 5 0 0 0 0 23443213 2 866 71 13 00 GPS 12 6 0 0 0 0 24500697 9 756 14 13 00 GPS 8 3 0 0 0 0 24642655 3 491 72 13 00 GPS 33 8 0 0 0 0 22809923 2 464 46 13 00 GPS 75 8 0 0 0 0 20313535 9 233 10 13 00 1 2 3 4 5 6 8 Chan is the simulator channel number Note Channels are displayed here as 1 to 12 but held internally as O to 11 system messages will use the internal channel numbering Type indicates satellite type either GPS or SBAS SVID denotes the satellite s space vehicle ID PRN denotes the pseudorandom noise sequence associated with the satellite Elev and Azim are the elevation and azimuth of the GPS SBAS satellite as viewed from the vehicle position Tropo Delay m and lono Delay m are the additional signal delays experienced by a G
21. either time into run to apply command or if command is applied when received vehicle antenna is always v1_a 1 for SimPLEX on 1 power ON 0 OFF chan either channel number 0 to 11 or satellite ID number 1 to 32 by chan 1 prev field is channel number 0 b prev field is satellite ID 1 apply to all channels satellites 0 only to the one specified all chans examples 0 00 00 10 POW_ON v1_a1 1 0 1 1 turn ON all channels 10 secs into run POW_ON v1_a1 0 0 1 1 Turn OFF all channels now timestamp veh_ant as above mode 0 absolute power 1 relative to current simulation power chan channel or satellite number by chan 1 channel 0 satellite all_chans 1 apply to all chans O apply to specified chan satellite only 63 DGPOO603AAA 1 07 Set power timestamp timestamp veh_ant as above level POW_LEV level power level dB w r t Stanag min veh_ant or offset in dB depending on mode level chan channel or satellite number chan by chan 1 channel by_chan 0 satellite all_ chans all_chans 1 apply to all chans absolute 0 apply to specified chan satellite only absolute 1 absolute power level O relative to current simulated power Example POW_LEV v1_a1 10 5 23 0 0 1 Set power level on satellite 23 to an absolute level of 10 5 dB immediately Note Use of the absolute flag in the POW_LEV command deems POW_MODE command obsolete Set PRN tim
22. file and repeat i e loop forever running the 2 scenarios alternately 8 3 COMMANDS VIA AN IEEE 488 INTERFACE For this option a National Instruments IEEE 488 card must be installed in the PC running the SimPLEX software PCMCIA version for a laptop PCI version for a desktop together with the National Instruments NI 488 2 driver software With the IEEE bus option enabled via the Remote Commands Settings menu shown above the SimPLEX software effectively becomes a talker listener instrument at address 1 by default An external computer equipped with an IEEE 488 interface and acting as a Bus Controller may control it by issuing any of the commands listed in section 8 1 above In addition the Bus Controller may read a serial poll status byte from SimPLEX by performing a serial poll or ibrsp operation This status byte contains the simulation state as follows Bits 0 to 2 simulation status 000 No scenario specified 001 Invalid scenario 010 Initialised 011 Arming STR4500 User Manual 65 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 100 Running 101 Paused 110 Ended Bit 6 is specified in the IEEE 488 standard as the SRQ flag but this is not used at present i e the SimPLEX software will never raise a service request SRQ To assist users in writing their own control program or incorporating SimPLEX STR4500 control into an existing program the source code for a simple example pro
23. roll over event The week number will roll over again at midnight 6 to 7 April 2019 Converting these numbers to a date and time will give the GPS time Note that this is not the same as UTC time Universal Time Co ordinated or GMT Greenwich Mean Time GPS time is continuous whereas UTC GMT is occasionally adjusted to synchronise time with the physical rotation of the earth around the sun In the GPS system the current difference between GPS time and UTC time is transmitted in the nav data message as a UTC offset integer seconds plus a fractional part plus information on recent or upcoming UTC adjustments SPIRENT simulations always set the fractional difference to 0 The integer difference UTC offset may be set non zero but is 0 in the default case The UTC offset for a given scenario may be found in the NAV_SAT TXT file F 2 TROPOSPHERIC AND IONOSPHERIC DELAY The GPS signals in space travel at the speed of light however they experience additional delays in the ionosphere and troposphere as they travel to a receiver on the earth s surface At scenario generation Tropospheric and lonospheric modelling may be turned OFF no extra delays FIXED fixed delay added or MODELLED In MODELLED mode one of various models may be selected The default case is to use the ionospheric model specified in CD GPS 200 and STANAG 4294 and the tropospheric model specified in STANAG 4294 STR4500 User Manual 97 Spirent Communications Lim
24. 0 MHz whichever value is greater aoe of L1 Referred to unmodulated lt carrier Close to Carrier Integrated between 10Hz lt 0 02 unmodulated and 10kHz RMS max phase noise Single Sideband Nominal signal Main RF port level CAL port approximate 70 dBm linear resolution 0 5 dB o ee ae oe Acceleration Maximum Relative Jerk 500 ms a ee e 1 5m lever arm frequency Modulation C A code ranging GPS PRN 1 37 SBAS PRN 120 138 GPS Data Bit Rate SBAS Data Symbol Rate Channel Hardware 100 Update Rate The STR4500 provides both the normal front panel RF output port RF OUT for testing and a high level rear panel output port CAL OUT to allow calibration Both ports are isolated to dc voltages STR4500 User Manual 113 Spirent Communications Limited 2002 DGPO0603AAA 1 07 1PPS OUT to RF Timing Uncertainty nsecs 16 between a rising transition RSS on 1PPS OUT port and its corresponding event on the Primary RF port ref 1PPS OUT 1 5v into 50 ohm Maximum time of 24 Hours simulation run K 3 ACCURACY PARAMETER DEFINITION Pseudorange Uncertainty in the SV code phase offset that 0 1 m RMS offset being calculated from range including ionospheric tropospheric delay and SV clock interchannel bias error derived by analysis Pseudorange rate Uncertainty in the rate of change of 0 01 m s RMS pseudorange measured with respect to the simulator reference oscillator 0 0
25. 0 User Manual Spirent Communications Limited 2002 1 07 T TCP IP network 84 TDOP 99 Technical Specification 109 Temperature 114 terrain obscuration 83 Time into run 19 time to first fix 68 time into week 97 Tool Bar Controls 37 TOOLS Menu 44 TRIG IN 10 11 TRIGGER 110 troposphere 31 tropospheric 72 TTFF 68 TURBO MODE ON OFF 37 U Universal Time Co ordinated 97 US Coastguard 99 USB driver 107 User Actions File 43 UTC 97 V VDOP 99 STR4500 User Manual Spirent Communications Limited 2002 DGP00603AAA Vehicle Dynamics window 21 W WAAS 7 warranty 79 website 79 week number 97 100 week number roll over 97 Weight 114 WGS ellipsoid 98 WGS 84 ellipsoid 30 Wide Area Augmentation System 7 WINDOW Menu 45 X XON XOFF flow control 50 Y YUMA almanacs 99 YUMA _ALM TXT 60 Z Z count 97 121
26. 01 m s RMS by analysis Measurement limit 0 05 m s RMS Delta apy a Uncertainty in simulating a change in satellite code phase over an interval by analysis Measurement limit 0 05 m RMS 0 005 m RMS carrier phase over an interval 0 05 m RMS phase delay shift due to ionospheric dispersion Interchannel Difference in the code phases at the RF output alignment between any 2 channels simulating the same 0 02m RSS satellite by analysis Measurement limit 0 1 m RMS Interchannel carrier Difference in the carrier phases at the RF output 0 005 m RMS t Dynamics lt 450m s 550m s gt i Dynamics lt 40m s 45mis gt 114 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO0603AAA PARAMETER DEFINITION alignment between any 2 channels simulating the same 0 265mm RSS Satellite Pseudorange Uncertainty in the rate of change of code acceleration frequency 0 005 m s2 RMS by analysis over gt 1s Pseudorange jerk Uncertainty in the rate of change of 0 02 m s RMS pseudorange acceleration over gt 1s by analysis Satellite signal level Uncertainty in the simulated power level per 1 0dB RSS channel Nominal level 15dB only 2 0dB Max 53mrad maximum Carrier Frequency Master clock may be manually adjusted to lt 8Hz to 158Hz at 0 05Hz error at calibration interval 1 year The L1 after 1 year unit can be phase locked to an external a
27. 03AAA 1 07 Double clicking the left mouse button on any of these windows produces a text window displaying complete vehicle motion data See Section 5 2 1 This Position data window may also be selected via the Menu Bar View gt Position Window or via the Tool Bar Window selection via the Tool Bar Power levels Power adjustment Antenna pattern Satellite data Sky Ground plot track TEA AR ta NON Vehicle dynamics NMEA out Time data NMEA in Position data RTCM out window 2 STR4500 User Manual Spirent Communications Limited 2002 NO 1 07 DGPOO603AAA 9 1 2 GROUND TRACK WINDOW The Ground Track window displays the ground track of the vehicle over the earth s surface and its current Latitude Longitude and Height Ground Track ae d 1 6 Latitude 50 19 500 Longitude 3 1 500 Height 100 00 m The X symbol shows the current vehicle position on a line representing the path the vehicle will take over the scenario s duration Tip To determine the direction of motion along the ground track look at the vehicle heading in the Vehicle Dynamics window which aligns with the current direction of motion STR4500 User Manual 23 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 Right clicking on the Ground Track window provides zoom in out options Holding down the left button allows a rectangular area to be selected On release the display zooms to
28. 232 INTERFACE This mode is not currently implemented This mode is selected by checking the RS 232 option on the Remote Command Settings menu and specifying an RS 232 port Setting RS 232 port characteristics is described in section 6 2 Operation in this mode is identical to that from a file as described in section 8 2 with the exception that the user may control the timing of when commands are issued Therefore timed commands may be prefixed with execute command now rather than an execution time as they must be in a file There is no message acknowledgement or status return in this mode This mode is not currently implemented STR4500 User Manual 67 Spirent Communications Limited 2002 1 07 DGPOO603AAA A MY GPS RECEIVER WON T NAVIGATE HINTS AND TIPS This is intended to help first time simulator users or those connecting a different model GPS receiver for the first time A 1 GENERAL CONSIDERATIONS When a GPS receiver navigates it will typically a Update its internal clock from GPS time b Store the acquired almanac describing the current satellite orbits in non volatile memory c Store its last known position in non volatile memory In normal use if the user switches on the receiver the next day it will expect its clock to still be close to GPS time It will also expect the stored almanac to be representative of the satellite orbits It may also assume that its position is l
29. 6 8155 bytes received successful 7 94 KBps 00 00 01 192 200 1248 Select the 4500 DATA subdirectory on the left hand pane to display its contents in the right hand pane To copy the desired ZIP and TXT files to your PC click on the FTP menu item at the top of the screen and select Local Browser This will display STR4500 User Manual 87 Spirent Communications Limited 2002 DGPO0603AAA 1 07 another pane with a directory tree for your local system You may need to select the Tile vertically icon to arrange the windows as shown below SmartFTP v 1 0 1998 2000 by Mike Walter ioj x ETP Script Commands View Tools Favorites Window Help BRO 5 G F QNGEQ S H a URL B SYSDEVICE GPSSIM iad Login gpssim Password Port 21 Anonymous ie Local Browser 1 ioj x a Cheyenne a Name E Common Files D 4500_3_CHANGE OVERS_V2 ZIP Data Access 4500_3_CHANGE OVERS_V2 TXT E Gms 9 Gss a a Str4500 9 Firmware Upgra E rtem_scen 3 scenarios E HTML Help Workshop E Internet Explorer m Ga hdenieMrowl hd 2 R1 D gt 3 192 200 1 248 a Name Size Date SYS SYSDEVICE 4500_24HOURS_DURATION_V3 TXT 512 bytes 12 05 0018 57 GPSSIM 3 4500_24HOURS_DURATION_ V3 ZIP 180MB 12 05 00 22 32 A 4500_DATA 2 4500_2HOURS_DURATION_ V1 TXT 512 bytes 18 05 00 15 57 a 4500_2HOURS_DURATION_
30. FE ABS and epoxy glass laminate 2 PHYSICAL FORM The equipment is housed in a vented aluminium enclosure Enclosure dimensions are 99mm h x 345mm qd x 254mm w approx Total weight of the Simulator Unit is 5kg approx 3 INTRINSIC PROPERTIES a Non operating Safe when isolated from primary power source b Operating Removing fixed panels during operation presents an electric shock hazard Fixed panels may only be removed by suitably qualified personnel High voltage hazard warning labels are affixed to the outside of the Unit WARNING This equipment must be earthed 4 FIRE CHARACTERISTICS Primary Overload conditions could present a fire hazard The limiting oxygen index value of the glass epoxy laminate is 25 32 Protection circuits incorporated minimise the overload and or component failure hazards The case is vented to minimise heat and gas concentration b Secondary Under overload conditions the external finishing paint will burn Excessive overload heating of materials will cause emission of toxic gases 5 HANDLING The unit is sensibly robust but dropping or excessive vibration may lead to immediate damage or later component failure with consequent damage The portable unit weighs 5kg approx The unit is supplied in an approved design package to minimise damage in transit 6 STORAGE Care should be observed when storing to ensure units cannot be subjected to environmental conditions in exc
31. Fools Window Help Format Simulated Data Hardware Settings 3 Logged Recetver Data Message Reporting Remote Command Settings ES232 Port Setting RATCOM Diferential Corrections User Actions File No Hardware Auto Repeat Run 5 4 3 1 No Hardware Check this option to run the software without driving the STR4500 hardware with or without the USB cable connected The No Hardware option is useful to preview a simulation especially in conjunction with Turbo mode See Section 5 3 5 4 3 2 Auto Repeat Run If you check this option before running a scenario then the next scenario run will be repeated continuously Selecting it while a scenario is running will repeat the running scenario continuously There will be a short delay before repetitions as the files are closed then re opened and display data read The rules for user action files and log files are as follows e Ifa User Action file is read for the initial scenario it will be used for the repeat runs also e If Differential Correction messages simulated NMEA or receiver NMEA messages are recorded then they will be logged for each run but to the same file name so effectively only the last data sets will be saved 5 4 3 3 Format Simulated Data Allows simulation data to be formatted as NMEA format messages and written to a file or output via an RS 232 port Described in Section 6 3 STR4500 User Manual 39 Spirent Communications Limited 2002
32. HE HOLDER OF THIS DOCUMENT SHALL KEEP ALL INFORMATION CONTAINED HEREIN CONFIDENTIAL AND SHALL PROTECT SAME IN WHOLE OR IN PART FROM DISCLOSURE AND DISSEMINATION TO ALL THIRD PARTIES TO THE SAME DEGREE IT PROTECTS ITS OWN CONFIDENTIAL INFORMATION The HTML help is based on this manual but may be browsed on line The left panel provides a Contents List shown above and Index and Search facilities while the right hand panel displays the information selected The context sensitive help button on the tool bar will also index into the appropriate section of the on line manual STR4500 User Manual 47 Spirent Communications Limited 2002 1 07 DGPOO603AAA 6 SOFTWARE REFERENCE NMEA AND RTCM MESSAGES 6 1 INTRODUCTION NMEA 0183 defines a standard set of navigation messages for GPS receivers In addition many applications and utilities accept data in this format RTCM SC104 defines a set of differential correction messages for enhanced GPS navigational accuracy The software provides the following NMEA and RTCM facilities a Simulation data may be formatted as NMEA messages and written to an ASCII file or output to an available RS 232 port during a simulation b NMEA messages may be logged from a receiver via an RS 232 port to an ASCII file and displayed in a message window during a simulation The receiver must have an available RS 232 output and NMEA message generation capability for this option c RTCM differential c
33. HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 1 HLT 0 ZCNT 9 SVID 2 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 4 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 5 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 7 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 8 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 9 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 10 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 13 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 24 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 9 SVID 26 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 19 SVID 2 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 1 07 19 SVID 4 PRC 0 0000009 2 RRC 0 0000006 3 IOD 2 UDRE 0 1 The RTCM standard defines that the data is actually transmitted in a 5 bit per character format so connecting a terminal to the RS 232 port to view the data will NOT produce data as displayed above It will produce printable but meaningless characters 2 The ZCNT Z count field shown in the messages above shows message time in 0 6 second units as specified in the RTCM standard Other programs or GPS receivers may display the z count in seconds or other units 56 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA
34. ING THE SimGEN FOR VMS AND SimGEN SOFTWARE SUITES D 1 INTRODUCTION Users equipped with SPIRENT s SimGEN For VMS software 6 80 or later running on a Alpha workstation or SPIRENT s SimGEN software suite running ona PC have the capability to generate scenarios for SimPLEX STR4500 In this mode features not accessible when requesting scenarios from the SPIRENT web site are available These include Multipath Ability to specify multipath signals Navigation Message Set message bits explicitly set parity errors and satellite health fields Vehicle motion Control of trajectory velocity terrain obscuration sea State for ships antenna position and orientation GPS constellation Control of orbital parameters signal characteristics ionospheric and tropospheric modelling clock noise model etc WAAS Control of satellite placement signal and message characteristics Terrain obscuration Differential Corrections Control of message types contents and rates Please review the appropriate SimGEN or SimGEN For VMS Reference Manuals for more details 1 Planned for Q103 STR4500 User Manual 83 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 D 2 DOWNLOADING THE SCENARIO D 2 1 SimGEN FOR VMS As the Alpha workstation is running the VMS operating system and the STR4500 PC is running either Windows 2000 or Windows xP the recommended method of file transfer is by FTP File Transfer Protocol over a TCP IP
35. MA format are available from the US Coastguard site at http www navcen uscg mil gos default html as well as other sites Each scenario includes its GPS satellite almanac in YUMA format in the file YUMA_ALM TXT A sample YUMA almanac for a single GPS satellite is shown below shee Week O94 Almanac Tor PIN 0L SANTE EREE ID gogog Health O00 BCCeENUCrICLeyY 0 Q00000000e 00 Time of Applicability s 0 Q000000000e 00 Orbital Inclination rad 9 599310887e 01 Rate of Right Ascen r s 0 000000000e 00 SORT A ime Ly 2 2 5 153700811e 03 Right Ascen at TOA rad 5 532693729e 00 STR4500 User Manual 99 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 Argument of Perigee rad re One OLCHORGNONGR ORONO r eNO Mean Anom rad 4 899139210e 00 AfO s 0 000000000e 00 AE I Core ic 0 Q00000000E4F0 0 week 894 Note that the week number is ambiguous See Appendix F 1 and must be resolved from information such as the start time of the scenario some receivers allow almanacs to be loaded directly allowing them to acquire satellites and navigate more quickly from start up when they do not already hold current almanacs in memory The YUMA_ALM TXT file is provided so that the user may download it to a receiver if he wishes F 7 GPS NOMINAL SIGNAL LEVEL The GPS nominal signal level is 130 dBm Where simulation signal levels are quoted in dB it is with respect to this level This signal level is define
36. Note that the ZDA message includes time zone information The ZDA messages produced here use the simulated longitude to extimate time offset every 15 degrees of longitude being taken as 1 hour time offset This is NOT accurate NMEA MESSAGE TIMING NMEA messages are output slightly early this means that they could be used to generate on time external aiding if desired For comparison with receiver under test NMEA messages the message time stamps should be used and messages with similar time stamps compared Typical message timing is shown in the following diagram Note that message duration is dependant on message length and baud rate selected 52 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO0603AAA t 0 scenario start SimPLEX NMEA output message t 1 timing Gated 1PPS signal g D NMEA GGA message on RS232 at 1 Hzrate Timestamp t0 Timestamp tl Timestamp t2 Approx 80 ms for 9600 baud rate Timing of TO message is somewhat variable depending on when Run button is pressed Run command sent in relation to 1PPS but is typically lsecond to 1 3 seconds before first IPPS rising edge t 0 STR4500 User Manual 53 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 6 4 LOGGING NMEA MESSAGES FROM A RECEIVER This option must be set before the simulation is started From the Menu Bar select Options gt Logged Receiver Data Logged receiver data NMEA x NMEA messag
37. PS SBAS signal as it passes through the troposphere and ionosphere See Section F 2 for details on tropospheric and ionospheric modelling options at scenario generation time STR4500 User Manual 31 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 Pseudorange m is the simulated signal delay in metres This includes the delay due to the free space distance between the GPS satellite at time of transmission and the receiver at time of reception plus any tropospheric and ionospheric delays plus any other errors or effects added at scenario generation PR Rate m s is the rate of change of pseudorange Power dB is the current simulated power relative to the nominal GPS minimum See Section F 7 32 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 5 2 4 POWER LEVEL ADJUSTMENT WINDOW m Power Levels Adjustment PRN Current Power Slider Value 15 10 0 10 20 Absolute Relative Signal Off nm i T All Channels Use the mouse to drag the sliders or simply click on the scales either side of the slider to increment decrement by 2 dB This allows adjustment of the signal level for each simulated satellite Note that where signal levels are quoted in dB they are with respect to 130dBm as described in Section F 7 Two modes are availab
38. SYNTAX Select SC filename looks in current directory if no path specified scenario including _ Example path SC C scenarios my sim May be called before a scenario has been run or after it has been rewound Set trigger Select trigger mode mode where n 0 software trigger 1 Ext trigger immediate 2 Ext trigger on next 1pps edge Run Runs selected scenario requires external scenario pulse to start in trigger modes 1 2 End run timestamp End running scenario EN 1 timestamp is either time into run to apply command or if command is applied when received Optional parameter not specified or 0 stop scenario leave at ENDED state 1 stop scenario and rewind to INITIALISED state ready to run again 2 stop scenario rewind to INITIALISED state rewind remote command file and repeat command sequence in it only applies to remote commands from file Rewind Called after scenario has been stopped by an EN command with optional parameter not specified or 0 rewinds scenario ready to run again or another scenario may be selected and run 62 STR4500 User Manual Spirent Communications Limited 2002 1 07 Power ON OFF Set power mode timestamp POW_ON target_ vehicle_and antenna on chan by_chan all_ chans timestamp POW_MODE veh_ant mode chan by_chan all_ chans STR4500 User Manual Spirent Communications Limited 2002 DGPOO0603AAA where timestamp is
39. SimPLEX gt GSS_Flash_Loader Note This utility must not be run at the same time as the main SimPLEX application Before running this utility ensure the STR4500 hardware is connected and powered on A file selection window is displayed Select the upgrade file supplied by SPIRENT and then click Load A message will be displayed when the upgrade has been downloaded Exit the application Power to the STR4500 must be now be cycled When the STR4500 powers up again the upgrade is complete The current firmware issue may be checked using the Options gt hardware settings menu item on the SimPLEX software STR4500 User Manual 107 Spirent Communications Limited 2002 1 07 DGPOO603AAA J RE INSTALLING THE SIMPLEX SOFTWARE J 1 FIRST TIME INSTALLATION The software is provided on CD ROM Insert this into the CD ROM drive If the Setup program does not start automatically double click SETUP EXE from the directory window for your CD ROM drive Follow the on screen instructions The installation program also installs the USB driver files for the STR4500 The first time the STR4500 is connected to the PC via USB the operating system registers the driver A New Hardware Detected message is displayed at this time While the STR4500 is connected you may examine My Computer gt System gt Device Manager and check under the USB entry GSS STR4500 GPS L1 Simulator should be visible By default the installation program installs
40. Specification Appendix K STR4500 User Manual 9 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 2 2 1 FRONT PANEL power supply Is operational error in which case it flashes ae ON when a simulation is in progress Flashes when awaiting an external trigger signal on rear panel TRIG IN ane RF Output connector 10 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 2 2 2 REAR PANEL IMPLT RATINGS Wiw AMG 4B BG OBA A FUST TOW MEAC 4 5 ULACIA PMV RAG 4B BR A WA FUSE TOH PA A S IE MON CAL EXPANSION ao OUTPUT eet PORT f WARNING ISOLATE WANS BEFORE SERVICING E z Type Description Provides a high level version of the connector front panel RF output PORT type 103 TRIG IN BNC Allows an external trigger signal to start a simulation 10 MHz OUT Internal reference output EXT REF IN BNC Allows unit to be locked to an external frequency reference 1PPS IN External system synchronisation input 1PPS OUT BNC External system synchronisation output HOST PC USB downstream connector in switch fuse Further details of these connectors are given in Appendix K STR4500 User Manual 11 Spirent Communications Limited 2002 DGPOO603AAA 1 07 2 3 PC AND SUPPLIED SOFTWARE The supplied PC is configured with Windows 2000 or Windows XP and the SPIRENT SimPLEX simulation software already installed The software is also supplied on CD ROM if reins
41. T Hardware Simulation Vehicle Current simulation time Greyed out if the No hardware option is selected See Section 5 4 3 1 SIMULATION STATUS Simulator can be in one of these states see BSED ARMING RUNNING PAUSED ENDED SHIP or SPACECRAFT 5 2 OTHER WINDOWS 5 2 1 POSITION DETAILS WINDOW The Position Details window displays vehicle position velocity and attitude data mm Position Details Position Position ECEF Velocity ECEF latitude 50 19 500 x 4074484 02 m vx 153 72 m s longitude 3 1 500 y 215317 41 m vy height 100 00 m z 4886024 41 m vz 127 69 m s speed 200 00 m s Attitude heading 0 0 000 elevation 0 bank 0 PDOP 2 36 Antenna Pattern File V1IAIPAT1 CSV STR4500 User Manual 29 Spirent Communications Limited 2002 DGPO0603AAA 1 07 The GPS system and SimPLEX use the WGS 84 ellipsoid to define the earth and an Earth Centred Earth Fixed co ordinate system referenced to this ellipsoid See Sections F 3 and F 4 for further details Vx Vy and Vz are the velocity components in their respective ECEF axes Speed is the velocity of the vehicle in its direction of motion DOP PDOP in the example shown is explained is Section F 5 The name of the Antenna Pattern file in use is also displayed on this screen The effect of the antenna pattern and how to specify an alternate pattern are described in Appendix E 9 2 2 ANTENNA PATTERN WINDOW This
42. U C Z RUN FROM Starts reading commands from a file in Remote REMOTE Command from file mode with the Start Remote task manually option selected Button is shown depressed when other remote modes are active TURBO MODE Selects deselects Turbo mode Turbo mode may be ON OFF useful to review a simulation before running it to preview the vehicle motion number of satellites visible over time and so on Turbo mode is only valid if the simulation software is being run without driving STR4500 User Manual 37 Spirent Communications Limited 2002 DGPO0603AAA 1 07 the STR4500 hardware See Section 5 4 3 1 Selecting turbo mode runs through the simulation at an increased rate dependant upon the turbo rate slider SLIDER Pauses the simulation only valid in Turbo mode Click again to resume simulation 5 4 MENU BAR File Wiew Options Tools Window Help 5 4 1 FILE MENU JES View Options Tools Window Open Ctro Close Open Close scenario file Rewing Burn Run controls as described in Tool Bar Turbo Made ti Pause section Stop He eee E seyret Shortcuts to open previously used E a een E ey 1 sim scenarios 3 det_v485 sim 4 example_scenarial sim Exit Exit from application 9 4 2 VIEW MENU Allows selection deselection of any available window plus Tool Bar and Menu Bar 38 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 9 4 3 OPTIONS MENU Smiem
43. User Manual Spirent Communications Limited 2002 IN OUT TYPE CHARACTERISTICS Provides the primary RF GPS signal output at specified levels 50 ohm VSWR lt 1 2 1 in band DC isolated Provides a high level output suitable for calibration with a power meter 50 ohm VSWR lt 1 AD 1 L1 DC isolated Allows the STR4500 to be locked to an external reference 10MHz or 5MHz sine square 5 to 10 dBm 1MHz square wave only O to 10 dBm 50 ohm Required ext ref accuracy lt 0 1 ppm 10MHz Sine 0 dBm nominal 50 ohm 111 DGPO0603AAA 1 07 PORT eet TYPE CHARACTERISTICS 1PPS IN 1 pulse per second USB IN OUT connector o In combination with the External Reference input can be used to synchronise the simulator to an external system TTL level compatible 50 ohm Main interface with PC Includes control data from PC and also 1PPS time synchronisation message to PC Universal Serial Bus bi directional A trigger input to allow an external signal to start the simulation TTL level compatible pues ohm 110 240V ac IN Industry Standard IEC 112 daaa switching No voltage selection required STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA K 2 SIGNAL CAPABILITY PARAMETER Ce UNITS Number ose GPS er ose sources In band spectral eee to unmodulated lt a kadia purity carrier level at RF output lt 160 dBm 1575 42 2
44. a ia Vlalsic cha ia vlals1c8 cha ia vlalsic9 cha ia vlalsica cha ia vlalsicb cha ia vlalslcc cha 2 yuma_alm tet Selected 0 files 0 bytes Total 20 files 1 945KB i re h STR4500 User Manual 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 09 02 00 13 193 330 193 330 193 330 193 330 193 330 193 330 193 330 193 330 193 330 193 330 0 0 16 648 95 599 96 606 95 666 93 843 97 107 94 349 103 968 94 834 94 654 96 305 0 0 2 269 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 You will be prompted for a destination drive folder Select the folder containing the sub folders for each scenario for a default installation this is C Program Files Spirent Communications SimPLEX Scenarios Also check the box use folder names on this menu this ensures the scenario is installed in its own directory The ZIP file set includes the appropriate sub folder and WinZip will create the folder it will have the same name as the scenario and unzip the files into it Note that the scenarioname TXT file is included in the ZIP set so there is no need to copy this separately to disk When the files have been unpacked exit the WinZip application 82 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA D BUILDING SCENARIOS US
45. ainties of the order of 100ns will exist In order to attain precise synchronisation it is necessary to supply the unit with an external 10MHz frequency reference and to observe certain timing requirements between the 1PPS IN and or TRIG IN signals and the EXT REF IN signal These requirements are detailed below STR4500 User Manual 75 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 B 2 B 2 1 B 3 76 Internal_10MHz_clock REQUIRED INPUT SIGNAL TIMING 1 PPS IN The required timing of the rising edge of 1PPS IN with respect to EXT REF IN and the resulting timing of the start of simulation is shown in the figure below Provided these timing requirements are adhered to the RF signal timing will be fixed and repeatable with respect to REF IN every time a simulation is run The EXT REF IN signal may be a square wave as shown for example a TTL CMOS signal or a sinusoid Whatever the REF IN input waveform the timing reference point is the ac zero crossing of the signal Notes 1 The alignment of 1PPS OUT as shown in the diagram does not occur immediately but one second after 1PPS IN is detected 2 Synchronisation to a 1PPS IN signal can only be achieved when the simulator is in the HALTED not running state Timing requirements for 1PPS IN thold 20 ns min tsetup 10ns min 1PPS_IN Ey EXT_REF_IN_ 10MHz One second later 1PPS OUT will be aligned as follows 1PPS_OUT Start of simulation
46. ations Limited 2002 DGPOO0603AAA 1 07 a SimPLEX ext_waas_test_v18 sim gt x File View Options Tools Window Help S 21 gt thor ole Em eal es ces Ball OEE Soran CEE OO EE latitude 50 19 500 x 4074484 02 m vx 153 72 m s umen ume 21 Aug 2000 18 00 00 End Time 21 Aug 2000 18 05 00 longitude 3 1 500 y 215317 41 m vy T ooo height 100 00 m 4886024 41 m vz 127 69 m s a EER a n speed 200 00 m s Se z count Attitude WN roll over heading 0 0 000 elevation 0 bank 0 Week number TOW PDOP 2 36 m Power Levels Adjustment Antenna Pattern File V1A1PAT1 CSY PRN Current Power Slider Yalue Chan Type SVID PRN Elev Tropo lono Pseudorange PRRate Power Delay m Delay m m m s 9B 15 GPS 39 6 0 0 0 0 22537630 7 279 96 13 0 10 GPS 15 4 24025972 5 542 36 13 0 GPS 16 3 24097494 5 414 03 13 0 GPS 4 7 25253146 4 615 00 13 0 GPS 37 8 21933891 6 476 11 13 0 GPS 23 5 23443213 2 866 71 13 0 GPS 12 6 245006979 756 14 13 0 GPS 8 3 24642655 3 491 72 13 0 GPS 33 8 22809923 2 464 46 13 0 GPS 75 8 20313535 9 233 10 13 0 0 10 20 g wu mn anh WON i oOo ke Oo fm a seooeeeee8 Soe of Oo eo cS ooo o oocdo oo amp O Absolute CN Se c Relative Signal Off Hig if ia ia ia9 ia ia iil T All Channels in System Messages 00 00 00 Info Ope
47. bsolute reference Master Clock Stability 1 x 108 Over Temp Range 5 x 140710 Over one day after 24hr warm up 1 x 107 Over one year continuous STR4500 User Manual 115 Spirent Communications Limited 2002 DGPOO603AAA 1 07 K 4 ENVIRONMENTAL For Signal Generator only Dimensions nom 254mm x 345mm x 99mm W x D x H 10inch x 13 6inch x 3 9inch Meow loom oo ooo Signal Generator 5kg 111b Temperature Operating temp 10 to 40 C 50 to 104 F Humidity 40 to 90 RH non condensing Storage temp Temperature 40 to 60 C 90 to 140 F Humidity 20 to 90 RH non condensing Electrical Voltage a c 100 to 120V RMS 220 to 240V RMS Power Consumption lt 70W Frequency 48 to 66 Hz 116 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA L CONTACTING SPIRENT United States Military and Government Canada Spirent Federal Systems 22345 La Palma Avenue Suite 105 Yorba Linda CA 92887 Contact Ed Schwanke Tel 817 401 0438 E mail edward schwanke spirentfederal com or help spirentcom com All other Regions and Customers Including US Commercial Spirent Communications SW Ltd Aspen Way Paignton Devon TQ4 7QR United Kingdom Contact Customer Support Tel 44 1803 546333 Fax 44 1803 546301 E mail help spirentcom com Access to the Spirent FAQ and document databases is via the Support web site This site also gives customers access to th
48. d 4 S P bUU a T 6 2 i A 10 D p j d 3 a gt Heading 0 x CLIMB 100 ft min oe N A Start Time 21 Aug 2000 18 00 00 Current Time 21 Aug 2000 18 00 00 End Time 21 Aug 2000 18 05 00 Time into run 00 00 00 Duration 00 05 00 Latitude 50 19 500 eee WN roll over 1 Longitude 3 1 500 A E Set Ramp Cancel Ramp Height 100 00 m TOW 100800 4 For Help press F1 21 Aug 2000 18 00 00 IN INTIALISED AIRCRAFT The following control bars are displayed at the top of the screen im SimPLEX ext_waas_test_v18 sim O Header Bar File Miew Options Tools Window Help sel w a gt tay al Menu Bar ee ee ee 3 a Tool Bar AIRSPEED mph i Ale 3 18 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA A Status Bar is displayed at the bottom of the screen 915x266 Set Ramp Cancel Ramp _ a Status Bar For Help press F1 Sat Feb 22 23 59 001997 Ramp Tool Bar detail Back to Start Turbo mode on and off 44 gt m Turbo speed Click the RUN button on the tool bar to start the simulation After a brief pause the ACTIVE LED on the STR4500 front panel will illuminate the Time into run field in the Data Time window will begin to increment and the simulation status on the Status Bar should display RUNNING That s it you are running y
49. d as the signal minimum level experienced by a receiver on the earth s surface from a GPS satellite on the horizon The satellite being in the standard GPS orbit position A in the diagram below GPS SATELLITE B GPS SATELLITE MINIMUM ge Ry N LEVEI EARTH 100 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA G CALIBRATION G 1 INTRODUCTION The STR4500 employs a digital architecture to produce accurate and stable signals As such it requires little calibration There are just two user adjustments Frequency and Power These are both simple potentiometer adjustments Test equipment requirements are a suitable frequency counter with a stable reference and an RF power meter respectively It is recommended that these calibrations be performed yearly AN Calibration involves operating the equipment with the casing removed and mains power applied Appropriate care must be taken These adjustments should only be performed by a suitably skilled person ic A Note Anti static handling precautions to be used throughout G 2 REMOVING THE STR4500 CASE a Ensure that nothing is connected to the front panel RF OUT connector b On the rear panel turn off the power switch and remove the power cord Remove USB cable and any other connections c Undo the four screws securing the rear panel bezel These are located near the rubber feet Remove the bezel d Undo the four screws secur
50. e CONTENTS HTM a table cross referencing which features appear in which scenarios This may be read using Internet Explorer or other HTML reader to determine which scenarios may be suitable for a particular requirement and then the relevant TXT files may be examined for more details as described above STR4500 User Manual 57 Spirent Communications Limited 2002 Global Simulation Systems STR4500 Scenarios Scenario Motion Location Errors Start SBAS Constellation Time RTCM Car Static mins Los No ISCH 03 00 None Week Read Unzip Angeles commencing 5 anes City Route ea P aah oan About This mins anag Iono Stops Turns 34N l aed This Scenario Urban accelerations 118W Stena Tropo Scenario then freeway Low Speed no multipath low obscuration Car Static 2mins Los Rnd fix sine 03 00 2x WAAS Week Read Unzip P Angeles ISCH commencing ath ae on F City Route About This mas Stops Turns 1 My Thi Scenari Ops Lurns 34N Stanag lono 2000 ins ocenario Urban accelerations 118W Scenario then freeway Stanag Tropo Low Speed indie no multipa low obscuration Car Static 2mins Los Rnd fix sine 03 00 2x WAAS Week Read Unzip Angeles ISCN commencing 5 aa e z l City Route About This mns Stops Turns ae Thi Scenari ops 1ums 34N Stanag Iono 2000 Anis scenario Urban accelerations 1183W Scenario then freeway Stanag Tropo Low Speed deik no multipa med obscuration
51. e complete Customer Support database system The support web site can be accessed via the Support links on our web site at http www positioningtechnology co uk STR4500 User Manual 117 Spirent Communications Limited 2002 1 07 10 MHz OUT 11 IPPS IN 11 110 IPPS OUT 11 41 109 A ACCURACY 112 active antenna 14 70 Active LED 10 almanac 68 antenna attenuation 93 antenna pattern editor 89 Antenna Pattern Window 95 attitude 91 B Back to Start button 19 BITE Reporting 105 Building Scenarios 83 C calibration 101 Carrier Frequency 111 113 Carrier phase delay 112 CD ROM 57 centre of gravity 91 Clock Noise 71 CofG 91 Contacting Spirent 115 CONTENTS HTM 57 D Date Time window 28 DC block 14 degradation 71 differential correction messages 49 STR4500 User Manual DGPOO603AAA INDEX Differential Corrections 83 Dilution of Precision 26 dipole 15 Diverge Clock 72 Diverge Ephemeris 71 DOP 26 98 E Earth Centred Earth Fixed 98 ECEF 98 EGNOS 7 ellipsoid 98 Engineering layout 45 ethernet 84 Expansion Port 11 EXT REF IN 11 41 External frequency 41 external reference 41 External Trigger 40 F false lock 70 FILE Menu 38 file selection 17 File Transfer Protocol 84 firmware 106 Flash memory 106 Frequency calibration 102 frequency standard 41 FTP 84 FTP site 81 FTP utilities 84 GDOP 99 geoid 98 GMT 97 Gre
52. ected and powered up although it is possible to run the software without the STR4500 present as explained in Section 5 4 3 1 This section demonstrates how to run the SimPLEX software It is not essential to connect a GPS receiver Double click on the SimPLEX shortcut on the desktop or select the SimPLEX program from the Start gt Programs menu The application will start briefly display a splash screen with the SPIRENT logo then display a file selection window Open 21x Look in i five_mins c ext_waas_test_v18 sim File name ext_waas_test_v18 sim Files of type SimPLEX Files sim Cancel Two scenarios example_scenario1 sim and example_scenario2 sim are always installed Scenario is a static simulation suitable for initial receiver testing Scenario2 contains moderate vehicle dynamics and better demonstrates how the software displays vehicle motion and attitude Select either of these scenarios By default scenarios are installed under C Program Files Spirent Communications SimPLEX Scenarios with each scenario installed in its own subdirectory which has the same name as the sim file STR4500 User Manual 17 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 This scenario will be loaded and the initial data for the simulation will be displayed EE ext_waas_test_v18 sim iel File View Options Tools Window Help cs O NA fas an nl fea AIRSPEED mph A 0 0 l 4 ba s
53. eeeeeeeeeeeeeeeeeees 97 STR4500 User Manual 5 Spirent Communications Limited 2002 DGPO0603AAA 1 07 F 3 F 4 F 5 F 6 F 7 G G 1 G 2 G 3 G 4 H J J 1 J 2 K K 1 K 2 K 3 K 4 L The ECEF co ordinate system ccccccccesseeeeeeseeeeeeeeeeeeeseeeeeens 98 The WGS 84 ellipsoid ANd QeOidS cceceeceeeeeeeeeeeeeeeeeaeeeees 98 DOP Dilution Of precision ccccccceeececseeeeeeeeeseeeeeseeeeseeeeees 98 YUMA almana S ressona aaa 99 GPS nominal Signal leVel cccccecceecseeeeeeeeeeeeeeeeeeeeaeeseeeseees 100 Calibra oM titanate atone wen eae eas ea eadine 101 MOGU Oe a eae mgt ous eeeesees Means 101 Removing the STR4500 case ccceeccceseeeecaeeeeeeeeeeeeseaeeeeens 101 Frequency Calibration cccccccccssececeseeeseseeceeseeeeesensseeeneuess 102 Power Level Calibration ccccccccseeeeeeeeeeeeeeaeeeeeeeeeeeeeeeeeens 103 BITEREPOUNO ninia tans aiadnebyalvncuias 105 Upgrading the firmware using the flash memory loader 107 Re Installing the SIMPLEX Software ccccseeeeeeeeeeeeeeeeeeens 109 FIRST TIME IMStallaviOnsciecsieiaiecesndeetetoninilecuidcaee a 109 Installing SimPLEX over a previous STR4500 Installation 109 STR4500 Technical Specification cccccccseccecseeeeseeeseeees 111 SIGNAL GENERATOR CONNECTIVITY ccceccceeeeeeeeeees 111 SIGNAL CAPAB IIT i eiee a 113 ACCURACY ssascenseateasnecch an A anus eee 114
54. election of a different file name or location End of simulation Ea Scenario ended User Actions File P 4800_scenarios air_mot_long my_user_actions act Browse M Save Logged Reciever Data file D 4500_scenarias air_mot_long NMEA_Rx_LOG TAT NMEA Simulated Data File P 4800_scenarios air_mot_long SIM_NMEATXT Browse VV Save RTCM Messages File D 4500_scenarias air_mot_long boo 5 4 4 TOOLS MENU ptons BBE window Help d4 Antenna Pattern Editor s Power Calibration E 2 Antenna Pattern Editor allows the user to edit antenna patterns see Appendix E Power Calibration allows the user to calibrate the signal generator power output see Appendix G 44 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO0603AAA 9 4 5 WINDOW MENU Toot EE i gt gt Cascade Tile Arrange Icons Detault Layout Engineering Layout cave Layout Restore Layout o 1 Date Time Selects and arranges windows Default layout resets the window display to that shown on application Start up Save Layout allows the user to define a custom screen layout select and arrange the windows as required then select Save Layout Use Restore Layout to recall the layout at any time Engineering layout resets the display to an alternative window set an example of which is shown in the following diagram STR4500 User Manual 45 Spirent Communic
55. eneration time the RX antenna is characterised as follows The position of the antenna may be specified with respect to the vehicle s centre of gravity CofG When vehicle motion is calculated the CofG position is propagated Antenna position is specified in terms of offsets in Metres along the vehicle s X Y Z axes from the CofG The attitude of the antenna may be specified with respect to the vehicle The following figure defines the vehicle X Y Z axes and the antenna azimuth and elevation co ordinates when no antenna attitude offset is applied 90 El 0 AZ 0 El Azimuth Plane The following figure defines the direction in which attitude offsets are applied STR4500 User Manual 91 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 Q Positive Bank Roll Positive Elevation Positive Heading The attenuation of the RX antenna is specified for signals arriving at any azimuth or elevation In practice this is specified as the attenuation at the centre of each 5 x 5 segment i e by a 72 x 36 element array of attenuation values mapped as follows Atten at 177 5 AZ 72 columns total Atten at 177 5 AZ 87 5 EL 87 5 EL Atten at 177 5 AZ 87 5 EL _ oe Atten at 177 5 AZ 87 5 EL 92 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA The total signal level is modified by the RX antenna attenuation The GPS
56. enwich Mean Time 97 Ground Track window 23 119 Spirent Communications Limited 2002 DGPOO0603AAA H handheld receivers 14 Hardware Settings 40 Harmonics 111 HDOP 99 health flags 72 Health LED 10 HELP Menu 46 Host PC 11 ICD GPS 200 8 installation program 107 Intentional Satellite Clock Noise 71 Interchannel alignment 112 Internet Explorer 57 ionosphere 31 ionospheric delay 72 IP address 84 ISCN 71 LED 10 M Message Reporting 42 Messages window 42 Modulation 111 MON CAL 11 15 103 MSAS 7 Multipath 83 N Navigation Message 83 NMEA 0183 8 49 No Hardware 39 parity 72 120 1 07 PDOP 99 Position Details window 29 potentiometers 102 Power LED 10 Power Level Adjustment Window 33 Power Level Calibration 103 Power Levels window 27 pre amplifier 14 Primary RF Output 10 PRN 31 pseudorandom noise sequence 31 Pseudorange 32 R RAIM 34 Ramp Window 34 Receiver Autonomous Integrity Monitoring 34 roll over 97 RS 232 Port Settings 50 RTCM SC104 8 49 Rubidium standard 102 RUN button 19 SA 71 Safety Notice 13 Satellite Based Augmentation Systems 7 Satellite Data window 31 SBAS 7 Selective Availability 71 Signal Dynamics 111 signal level 27 111 Sky Plot window 25 sky search 69 spectral purity 111 STANAG 4294 8 Status Bar 19 29 STOP button 19 STR2760 7 STR4760 7 support 79 SVID 31 STR450
57. ern or by clicking on the azimuth or elevation values at the top side of the edit area and entering a value the whole column row is set to that value When you have modified the antenna pattern use the File gt Save option to save your new pattern as a CSV file STR4500 User Manual 95 Spirent Communications Limited 2002 DGPOO603AAA 1 07 You may use the View gt Antenna Pattern Window option to view the resulting pattern The modified pattern will be applied the next time the scenario is run Note The software will always use the antenna pattern specified in the file named V1A1PAT1 CSV in the selected scenario s folder You may manually change antenna patterns by renaming the required antenna pattern to this name and copying it to the required folder Similarly you may wish to save a copy of the original pattern elsewhere before modifying the supplied pattern as described above 96 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA F MISCELLANEOUS GPS INFORMATION F 1 WEEK NUMBER Z COUNT AND GPS TIME In the GPS navigation data message time is specified as a week number WN and a time into week count in 1 5 second units Z count The week number field can take values from 0 to 1023 GPS time started on midnight of the 5 to 6 January 1980 Thus week 1023 ended on midnight 21 to 22 August 1999 At this point the week number re set to 0 the so called week number
58. es fram your GPs receiver may be displayed and logged to a file ou may also supply a file of initialisation commands to be sentto the reciever This file can be used to tell the receiver which NMEA mesages to transmit Forto use com W Enable Log NMEA messages to the following file C Program Files Gooio TR4S00 tom scen NMEA Re LOG TAT Browse V Enable Initialsaton data file CAProgram Files GSS S7TR4500 rtem_scen br _AMEA_INIT ra Browse W Enable i Check the Port to use Enable option then select the port required Check the Log NMEA messages to the following file Enable option and select the name and location for this file The default is a file named NMEA _RX_LOG TXT stored in the currently selected scenario s folder a Browse button is provided to change this The receiver may always output NMEA messages or may need to be commanded to do so These commands are often entered from its front panel control or via its RS 232 interface In the latter case enter the appropriate command strings into a text file check the Initialisation data file Enable button Enter the full pathname of this file or use the Browse button Each line in the file except lines starting with in column 1 which are comment lines is sent to the receiver before the simulation starts 54 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 6 5 RTCM DIFFERENTIAL CORRECTION MESSAGES
59. ess of those given in the relevant data Units should not be stored in conditions exceeding the temperature range of 20 C to 60 C 7 DISPOSAL Disposal of the unit should be accordance with the toxic waste disposal procedure current at the time of disposal Units must not be incinerated due to the presence of PTFE which would emit toxic fumes 8 UNSAFE USE Electric shock hazard is present if panels are removed during operation Fire hazard could occur during overload conditions Replacement fuses should be of the correct rating and type to minimise overload conditions Toxic fume hazard possible if unit is overheated from internal or external source Mechanical hazard can occur if the unit is mishandled or incorrectly secured Under damage conditions do not use STR4500 User Manual 13 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 3 2 SYSTEM INTERCONNECTIONS Connect the PC keyboard monitor and mouse as described in the manufacturer s instructions A the PC and or monitor may have a switchable A C power input Ensure that it is set to the correct voltage before connecting power The power input to the STR4500 is auto sensing Connect the power cord to the STR4500 Connect the supplied USB cable between any USB port on the PC and the HOST PC connector on the STR4500 Turn on the PC and STR4500 On the PC log on screen enter the User name gpssim and password nicola on sta
60. estamp timestamp as above code on off PRN CODE chan channel no 0 to 11 chan all_ chans 1 apply to all channels all_ chans O apply to specified channel only on 1 PRN code ON O PRN code OFF Note that SimPLEX must be activated and a scenario already selected before the remote commands can be actioned SimPLEX may be started with a pre selected scenario by running the SimPLEX exe executable passing a scenario name with path as a command line parameter 8 2 COMMANDS FROM A FILE Using the syntax described above a series of commands may be placed in an ASCII file with a file extension cmd to define a test sequence which may be run repeatedly or unattended Write the commands to a file select remote control and Enable remote control and start remote task manually and tick the enable box for Data file user actions and enter the path and filename for your file below it 64 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA To execute the command file click on the remote control icon on the toolbar Commented example command file comments are bolded and should NOT be placed in the file SC C scenarios example example sim select example sim RU run it 0 00 05 00 EN 1 halt run after 5 mins and rewind scenario SC C scenarios example2 example2 sim select example2 sim RU run it 0 00 05 00 EN 2 halt run after 5 mins rewind scenario and rewind command
61. evel Different colours are used for different signals and levels Positive levels are shown green levels from 0 to 15dB are shown blue and signals below 15dB or OFF are shown red Note that for signals below 15dB power level accuracy is not specified SBAS signals are shown in darker shades of these same colours Double clicking on this window displays the Power Levels Adjustment window which allows the signal levels to be modified by the user See Section 5 2 4 This screen may also be selected via the Menu Bar View gt Power Adjustment Window or via the Tool Bar STR4500 User Manual 27 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 9 1 5 DATE TIME WINDOW The Date Time window displays the time currently being simulated scenario start and end times and duration m Date Time start Time 21 Aug 2000 18 00 00 Current Time 21 Aug 2000 18 00 00 End Time e 1 Aug 2000 18 05 00 Time into run 00 00 00 Duration 00 05 00 count Ww roll over Week number Be TOW 100800 The Z count fields display the current simulated time in GPS format as described in Appendix F 28 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 5 1 6 THE STATUS BAR This bar is always present at the bottom of the SimPLEX display _ _ _ SS ee For Help press F Mon Aug 21 19 00 00 2000 Ay INITIALISED AIRCRAF
62. ft Scenario Request form depending on your requirement In the resulting login dialogue box see below enter user name as request and password as cb1ew3d both name and password are case sensitive You must login to request a scenario from this site User Mame Password The Terrestrial request form is shown overpage STR4500 User Manual 79 Spirent Communications Limited 2002 DGPO0603AAA 1 07 3 Spirent Communications Positioning Technology Microsoft Internet Explorer File Edit view Favorites Tools Help lt Back x fat A Search Ga Favorites media lt 4 E5 id Address http www positioningtechnology co uk scenario_terrestrial asp SS SP IRENT Analyze Assure Accelerate ss arch Home Products Solutions News and Events Service and Support Links Contact About Us Please complete ALL the fields in the form below to enable us to create a terrestrial scenario for you Contact Name July 2002 STR4760 Performance Company increase to 1 00Hz remote motion data Email Address June 2002 i Tr 6556560 Product Launched Unit Serial Number 12L1 with Scenario Generation Headlines june 2002 Describe the scenario you require below US User Conference Held Online help is provided by clicking on the field headings on the left Looking for STR4500 Scenarios Start Date o x January x 2002 Day Month Year Click Here Start Time oo
63. gram is included on the SimPLEX distribution CD This is named simplex_ieee_test 8 4 COMMANDS VIA A TCP IP SOCKET INTERFACE Selected by enabling the BSD sockets option on the Remote Command Settings menu This option allows either another program running on the same PC or on a remote PC connected via Ethernet and TCP IP to control the SimPLEX software The SimPLEX software acts as a server and the remote program as a client The SimPLEX software must be active and the BSD sockets remote control option selected before the client attempts to connect Once connected all the commands specified in section 8 1 may be issued Following each command write by the client a read command must be executed This will return simulation status information and the last fatal error message if there is one in the following format Status xx fatal error message text where xx is a hexadecimal number representing the simulation status as follows 00 No scenario specified 01 Invalid scenario 02 Initialised 03 Arming 04 Running 05 Paused 06 Ended To assist users in writing their own control program or incorporating SimPLEX STR4500 control into an existing program the source code for a simple example program is included on the SimPLEX distribution CD This is named simplex_sockets_ test 66 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 8 5 COMMANDS VIA AN RS
64. he SimPLEX software displays a DOP type and value and many receivers also display a DOP type and value These are a measure of the goodness of the positions of a set of four of the current GPS satellite positions in the sky for navigation The various DOP types relate to a navigation solution optimised for different applications 98 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPO0603AAA HDOP Best horizontal accuracy PDOP Best positional accuracy VDOP Best vertical accuracy TDOP Best time accuracy GDOP Best geometric arrangement of satellites best general solution The DOP type displayed by SimPLEX is determined at scenario generation time The receiver may display a different DOP type or it may be user selectable Selecting the same DOP type as the simulation should give good correlation of the DOP numbers although the receiver may select a different set of satellites and hence produce a different value depending upon its satellite selection algorithm Generally the lower the DOP value the better the navigation solution Values around 1 to 2 5 are good 9 is very poor F 6 YUMA ALMANACS An almanac describes the orbits of the GPS satellites Almanac data is transmitted in the Navigation Data message to allow receivers to calculate GPS satellite positions The YUMA format is a widely used ASCII format for recording and disseminating almanac sets Current and past GPS almanacs in YU
65. hieve a frequency reading of 10MHz 0 02Hz G 4 POWER LEVEL CALIBRATION This requires an RF power meter capable of measuring a frequency of 1 57542 GHz and power levels between 50dBm and 60dBm for example an HP E4418B Ensure that the power meter is calibrated according to the manufacturer s instructions including any adjustments for sensor calibration factor and frequency AN This procedure involves operating the equipment with the casing removed and mains power applied Appropriate care must be taken A utility is provided in the SimPLEX software to assist in this calibration To perform the calibration first ensure you are exited from the STR4500 software If you have not already done so remove the STR4500 case as described in Section G 2 and locate the Power adjustment potentiometer Reconnect the power and the USB connector and restart the SimPLEX software on the PC From the Menu Bar select Tools gt Power Calibration and follow the on screen prompts The software will set up a calibration signal on the rear panel MON CAL output and calculate and display the power level required on the power meter Adjust the potentiometer to obtain this value 0 05dB The calibration is then complete STR4500 User Manual 103 Spirent Communications Limited 2002 1 07 DGPOO603AAA H BITE REPORTING BITE messages are displayed in the message window see Section 5 4 3 6 Message types info fatal and warning contain
66. ied from start of simulation otherwise the ramp is applied immediately Again the user must ensure that the SV selected is currently present and will still be present on the same channel at the time of application STR4500 User Manual 35 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 The Ramp Up Time Hold Time and Ramp Down Time can be used to specify the error profile FN w PERIOD START TIME This facility may be used to generate the following pseudorange error profiles 36 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 5 3 THE TOOL BAR CONTROLS Many of the buttons display or remove specific windows these windows are described elsewhere See Section 5 1 1 The remaining buttons are described here Back to start Turbo speed Run running from remote Turbo mode on and off OPEN Displays the file open menu to allow a scenario to be selected ABOUT Displays software issue number HELP Context help Click left mouse button on icon then move the cursor to area of interest and click again for help on that item MESSAGES Displays the scrolling system message window Runs the current scenario STOP Halts the current scenario The last data displayed is held until Back To Start is clicked BACK TO Closes all files reads initial scenario data and gt oO O Cc a START displays it Performs the same function as the Rewind on the FILE MEN
67. ikely to be somewhere near its last known position If all these assumptions are true then signal acquisition and navigation may be very quick i e a rapid TTFF time to first fix When connected to a simulator all these assumptions may be false a The simulated date time may be very different from the receiver s time b The simulated almanac may be entirely different from the last almanac recorded Even if the almanacs are identical a different simulated time will place the satellites in different positions in the sky c The simulated position may be at the other side of the world from the last position recorded by the receiver STR4500 User Manual 69 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 If your receiver refuses to navigate the following actions are suggested a Do Nothing Typically the receiver will try to acquire satellites using its current data If it fails it will revert to a sky search mode looking for any satellite When it finds one it will attempt to extract the almanacs for all the other satellites from its Navigation Data message It will also typically update its date and time from this Navigation Data message A complete set of almanac data is transmitted by each GPS satellite every 12 5 minutes so once a single satellite has been tracked continuously for this period orbital data will have been obtained for all satellites If the receiver is still assuming its last known position it may i
68. information for SPIRENT use only Note Fatal messages will produce a pop up warning box and terminate a simulation if running Message type hardware contains BITE information generated by the STR4500 hardware All hardware messages except for the following will require the user to contact SPIRENT Displayed string User action RF Reference oscillator out of lock Check the external reference is connected and the hardware settings options are correctly set see Section 5 4 3 4 USB Error Check USB connection STR4500 User Manual 105 Spirent Communications Limited 2002 1 07 DGPOO603AAA UPGRADING THE FIRMWARE USING THE FLASH MEMORY LOADER The STR4500 internal firmware may be upgraded in the field SPIRENT may make upgrades available from time to time to customers under Warranty or a Support agreement Upgrades will be made available via suitable media or from an FTP site The STR4500 Flash memory device is capable of holding multiple application images A default image is loaded during manufacture and never overwritten Further images may be stored at different memory locations and may be overwritten many times The boot code will always check for a new image and run it if found If no new image is found the default image will be run The firmware may be upgraded in the field over the USB interface using a utility supplied by SPIRENT This utility is accessed from the Windows Start menu Start gt Programs gt
69. ing the STR4500 chassis into the case These are located at the four corners of the rear panel e Undo the two screws on the underside of the STR4500 case which secure the chassis Place unit correct way up on bench f Remove the chassis horizontally from the rear of the case avoiding any upward force STR4500 User Manual 101 Spirent Communications Limited 2002 DGPO0603AAA 1 07 The frequency and power adjustment potentiometers are located as shown in the diagram below AA G 3 FREQUENCY CALIBRATION This requires a frequency counter capable of measuring 10 00 MHz with at least 10 digits of accuracy for example an HP53131A The frequency counter should be locked to a frequency standard accurate to lt 1 x 10 for example an HP5065A Rubidium standard It is permissible to use a less accurate standard if the user is prepared to accept lower frequency accuracy for the simulator If you have not already done so remove the STR4500 case as described in section G 2 AN This procedure involves operating the equipment with the casing removed and mains power applied Appropriate care must be taken Reconnect the power cord and attach the frequency counter to the 10MHz OUT BNC connector on the rear panel Turn on the STR4500 Allow 15 minutes for the internal oscillator to stabilise 102 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA Use the frequency adjustment potentiometer to ac
70. ion is started From the Menu Bar select Options gt Format Simulated Data Formatted Simulation Data Settings sin nmea tet Select the message types required and their rate The start and stop times are with respect to the start of the simulation The start and stop times for message generation allow data to be captured over the specified period By default the messages are written to the file SIM_NMEA TXT in the current scenario directory but a browse button is provided to allow the user to select any file or directory STR4500 User Manual 51 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 To send the messages to an RS 232 port set the Enable flag and select the port If this port is already allocated you will be warned You may override the existing allocation or quit To view the messages as they are generated go to the Menu Bar and select View gt NMEA Simulated Data This will display the Simulation Data NMEA Simulated Data Messages window a NMEA Simulated Data Messages GPGGA 180000 00 5019 49999 N 00301 50000 W 8 10 2 4 50 4 M 49 6 M 4D GPGLL 5019 49999 N 00301 50000 180000 00 A A 7C GPGNS 180000 00 5019 49999 N 00301 50000 W AN 10 2 4 50 4 49 6 61 GPHDT 0 0000 T 05 GPGGA 180030 00 5022 73632 N 00301 50000 W 8 10 2 4 50 4 M 49 6 M 41 GPGLL 5022 73632 N 00301 50000 W 180030 00 A A 70 GPGNS 180030 00 5022 73632 N 00301 50000 W AN 10 2 4 50 4 49 6 6D GPHDT 0 0000 T 05
71. ited 2002 DGPO0603AAA 1 07 To find out which model was used for a particular scenario use Wordpad or an equivalent editor to open the file NAV_SAT TXT in that scenario directory and examine the relevant fields Some GPS receivers allow you to specify the model to use or to turn modelling off In this case matching the receiver s setting to the simulation should produce the most accurate navigation solution F 3 THE ECEF CO ORDINATE SYSTEM The simulator displays positional data as latitude longitude and height and as X Y Z values in the ECEF Earth Centred Earth Fixed co ordinate system This system has its origin at the centre of the earth its X axis passes through the intersection of the equator and the Greenwich meridian the Y axis passes through the intersection of the equator and the 90 East meridian and the Z axis through the North Pole The centre of the earth is as defined by WGS 84 F 4 THE WGS 84 ELLIPSOID AND GEOIDS The GPS system uses the WGS ellipsoid and the simulator displays latitude longitude and height based on this ellipsoid Some receivers may display position based on a local ellipsoid or geoid If the receiver may be set to use the WGS84 ellipsoid then doing so will produce the best correlation between simulated and receiver position If not then it is possible to calculate the equivalent position in the required geoid ellipsoid given the WGS 84 position or vice versa F 5 DOP DILUTION OF PRECISION T
72. lator and the remainder of a user s system This appendix describes how to use the 1PPS IN and or TRIG IN inputs to achieve synchronisation See section 5 4 3 4 for information on checking and or changing the current hardware settings The STR4500 simulator maintains time internally by means of a time counter clocked by an internal 10MHz clock Simulations always start on a one second rollover of this timer The timer may be synchronised to an external system before starting a simulation by applying a rising edge to the 1PPS IN rear panel input Once this has been done simulations may be started either by appropriate timing of the software run command Trigger Mode Disabled or by selecting Delayed Trigger Mode and applying a rising edge to the TRIG IN input Both cause the simulation to start on the next one second rollover of the timer Alternatively the user can select Immediate Trigger Mode which forces the timer to a point just before the one second rollover and freezes it until a rising edge is detected on the TRIG IN input whereupon the simulation starts running after a short delay Note that the use of TRIG IN immediate mode together with 1PPS IN is inappropriate as both would be attempting to control the timer however TRIG IN delayed mode can be used with 1PPS IN If coarse synchronisation to the user s system is sufficient the above methods may be used with no additional considerations however certain fixed delays and uncert
73. le Absolute and Relative In Absolute mode the signal levels from the simulation files are ignored and the level set on the sliders is directly applied to the output signal In Relative mode the slider values are taken as OFFSETS from the signal levels specified in the scenario slider values are added to the normal simulated signal levels This mode would typically be used to preserve the signal level differences between channels Use the All Channels check box to adjust all channels simultaneously For example to increase the level of all channels by 10dB to compensate for the omission of a pre amplifier in the test set up select All Channels and Relative mode and adjust any slider STR4500 User Manual 33 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 Note that if the base signal plus offset exceeds 15dB then the signal will be truncated to 15dB Each channel may also be switched OFF using the Signal Off check box In this case the signal level is displayed as OFF in the Power Levels window When scenarios are generated signal levels may be set FIXED or MODELLED The signal level is also modified by the Antenna Gain Pattern see Appendix E 9 2 9 RAMP WINDOW PSEUDORANGE MODIFICATION This window is displayed by clicking the Set Ramp button on the Sky Plot window It allows a Pseudorange error profile to be added to the signal for the specified SVID Only one SVID may have a pseudorange ramp applied at any one ti
74. lective Availability SA feature of GPS which is normally present for real GPS satellites Clock Noise Disabled Enabled plus Intentional Satellite Clock Noise Data tables showing model selected and parameter values for each satellite e Have deliberate Along Down or Across Track errors been applied Track Errors ov Along Cross Down m m m Ol Q Q000 2000 Fso il 12 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 02 O 2000 0 000 OOOO e Are Satellite Clock errors applied Diverge Clock Disabled Enabled plus Clock Divergence Terms in the Satellite Configuration section e Have bad health flags corrupted data or bad parity in the GPS navigation data been set as these can affect receiver accuracy or stop the receiver using that satellite OL All data OK plus any nav data modifications made in the Edit Nav Data section e Does the simulation apply tropospheric and ionospheric delay models These may be different from the ones used by the receiver Alternatively tropospheric and ionospheric modelling may be turned off in the scenario but enabled in the receiver It is possible on some receivers to specify different tropospheric and ionospheric models Specifying the same model or no modelling to match the simulation should result in best accuracy See Appendix F
75. me This may be used to test a receivers RAIM Receiver Autonomous Integrity Monitoring facilities or to examine the effect of a deliberately introduced error Satellites displayed on the skyplot marked with an R indicate an active ramp is applied To cancel an active ramp click the Cancel Ramp button on the skyplot window 34 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO0603AAA 1Pseudorange Ramp and Step x This dialog allows you to apply a pseudorange error to a gien satellite PRN z Fseudorange change You can apply the error immedately or at a specific time from the beginning of the sceanrio R o days 00 00 000 fou can initially apply the full error or have the error build up then reduce over time Ramp Up Duration o 7 days 00 00 00 Hold Duration i days 01 00 00 Ramp Down Duration o days 00 00 00 Enter the PRN of the GPS satellite SV to which the ramp is to be applied Note The user must ensure that the selected SV is currently being simulated No checking is applied on this field On exiting the ramp screen all channels are checked to see if the chosen SV is present if not the ramp command is ignored A satellite with an active ramp is denoted by an R adjacent to it on the Sky Plot Pseudorange change is the offset that will be applied during the Hold Time Select the Use Start Time check box to apply the ramp at the time specif
76. mmand successful STR4500 User Manual 85 Spirent Communications Limited 2002 DGPOO603AAA 1 07 150 Opening data connection for DKAIO0O ICB 4500 DATA MYSCEN ZIP 1 192 200 1415 1674 226 Transfer complete ftos 975572 bytes received im 1 32Seconds 739 0 7Roytes sec ftp gt quit 8 221 Goodbye D Temp2 gt Notes 1 Enter the workstation s I P address or node name 2 Enter the username for the workstation account required normally gpssim 3 Enter the account password nothing will be displayed on the screen 4 The DIR command allows you to view available files Files for transfer will be in the GPSSIM 4500_ DATA directory 5 Use the GET command to copy the specified file to your current directory 6 Having copied the TXT file using default transfer mode the ZIP file must be copied in binary mode 7 Use the GET command to copy the ZIP file 8 Quit the FTP program which will close down the connection to the workstation before exiting Now copy the files to the appropriate directory if you did not FTP them to the correct directory and unzip as described in Appendix C 2 D 2 2 DOWNLOADING USING SMARTFTP To use Smart FTP run the utility then enter the Alpha system URL IP address account name and password The URL is 192 200 1 248 and the account GPSSIM in the following example 86 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA Smar
77. n is displayed and the request is e mailed to SPIRENT Once your request has been accepted by SPIRENT an e mail will be sent to the address you specified acknowledging the request and informing you when the scenario will be ready normally within 2 working days When SPIRENT has generated the scenario a further e mail will be sent containing the URL address from where the scenario files can be down loaded via FTP and the names of the files The scenario will remain at the URL address for at least 3 weeks or until you inform SPIRENT that you have successfully transferred the files C 2 UNZIPPING A SCENARIO FILE Having downloaded the scenario to your PC the scenarioname ZIP file must now be unzipped A licensed copy of WinZip http Awww winzip com is installed on the PC Use this to unzip the scenario Simply double click on scenarioname ZIP in Windows Explorer to start this application The contents of the ZIP file are displayed Click on the Extract icon to extract the files WinZip EXT_WAAS_TEST_ 11 ZIP File Actions Options Help e 9 eevee sds New Open Favorites Add View CheckOut Wizard 7 ext_waas_testvl 09 02 0013 640 73 Se rtcrn dif 09 02 00 13 21 001 2 120 a 09 02 00 13 496 26 09 02 00 13 672 45 09 02 00 13 9 686 1 258 09 02 00 13 5 804 261 09 02 00 13 2 900 83 la vlals1 sig ia vlalsicl cha ia vlals1c2 cha ia vlalsic3 cha ia v1als1c4 cha ia v1als1c5 cha ia v1als1c6 ch
78. narios for cars ships aircraft and orbiting spacecraft SPIRENT also offers a service for custom simulation generation Users with access to a SPIRENT STR2 760 or STR4 760 GPS Simulator system can generate compatible simulations for download to an STR4500 Production extended test duties may then be performed by the STR4500 freeing the STR2 60 or STR4760 for development roles STR4500 User Manual 7 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 1 1 REFERENCED DOCUMENTS a ICD GPS 200 The document defining the GPS system space and user segments b STANAG 4294 The NATO equivalent of the above document c NMEA 0183 Document defining a standard set of navigational messages supported by many GPS receivers d RICM SC104 Document defining a set of differential correction messages accepted by many GPS receivers 8 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 2 SUPPLIED ITEMS 2 1 ITEMS LIST STR4500 GPS SBAS Simulator Windows 2000 Windows XP PC with SimPLEX Simulation software installed system may be supplied with notebook PC User Manual This book SimPLEX Simulator software and scenarios on CD ROM USB cable Power cables Country specific SPIRENT mouse mat NO Sp a 2 2 STR4500 SIMULATOR INDICATORS AND CONNECTORS This section gives a brief overview of the indicators and connectors on the STR4500 Signals are fully characterised in the Technical
79. network connection The Alpha workstation generating SimPLEX STR4500 scenarios must either be connected on the same local network as the PC connected directly to the PC Ethernet port using a cross pinned cable or on a remote network that may be accessed from the SimPLEX STR4500 PC It is assumed here that the workstation is configured to run TCP IP has a valid IP address and is connected to the same local network as the PC If this is not the case consult local VMS support if available the VMS documentation supplied with your workstation or the 2760 4760 Reference Manual To check for TCP IP support on your Alpha workstation type the following command S show net For a system with TCP IP networking a message similar to the following should be displayed Product TCP IP Node ALPSER GGSL CO UK Address es 192 200 1 204 Various shareware or freeware FTP utilities are available that make file transfer easier Examples are Cute FTP a shareware product available at http www globalscape com or Cupertino FTP a freeware product at http members xoom com CupertinoFTP Systems supplied by SPIRENT are supplied with a freeware FTP utility called SmartFTP Alternatively there is a basic command driven FTP utility available under Windows2000 Its use is described below Much of the information will be relevant when using graphical FTP utilities such as SmartFTP Start up a Command Prompt window terminal emulating window using Start g
80. ning simulation file ext_waas_test_v18 sim 00 00 00 Debug No satellite on channel 11 00 00 00 Debug No satellite on channel 12 v 4 gt For Help press F1 21 Aug 2000 18 00 00 TEA INITIALISED AIRCRAFT 5 4 6 HELP MENU wincio gt gt Help Topics About simPLE About SimPLEX displays a splash screen which includes the software issue Help Topics provides access to the on line HTML help documentation 46 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 4 Hide Back Home Print Options Contents Index Search Mam 2 Supplied Items 2 Items List STR4500 Sinmlator Features and Connectors 2 PC and Supplied Software 2 Cormecting The System pe STR4500 GPS SBAS SIMULATOR 2 System Interconnections 2 Connecting Your GPS Receiver 2 Running Your First Simulation USER MANUAL 2 Software Reference Main Functions AA The Defaut Windows B Vehicle Dynamics Window 2 Ground Track Window 2 Sky Plot Window 2 Power Levels Window 2 DatelTime Window 12 The Status Bar H Other Windows 2 The Tool Bar Controls QJ Mem Bar 2 FILE drop down 2 VIEW drop dowm 7 OPTIONS drop dowm 2 TOOLS drop down 2 Windows Drop Down PROPRIETARY INFORMATION THE INFORMATION CONTAINED IN THIS DOCUMENT IS THE PROPERTY OF GLOBAL SIMULATION SYSTEMS LIMITED EXCEPT AS SPECIFICALLY AUTHORISED IN WRITING BY GLOBAL SIMULATION SYSTEMS LIMITED T
81. nitially search for satellites that are expected overhead according to the new almanac It should eventually resolve these issues and produce a correct position b Reset Initialise the receiver Many receivers have an INITIALISE or RESET function This will typically clear any stored almanacs and the last Known position and force the receiver into a sky search mode c Help it out The receiver may allow the user to enter information to help it along This may include any of the following Re set the receiver s date and time to the simulated date and time This need not be to the exact time within a few minutes is acceptable Re set the receiver s last known position to the simulated position Again this need only be approximate Download the simulation almanac to the receiver Some receivers allow this via an RS 232 port or some other mechanism The simulation almanac is available in a common ASCII format See Appendix F 6 When a receiver has navigated once from a given scenario repeating that scenario should result in much quicker acquisition as the almanacs will be current 70 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA A 2 SIGNAL LEVELS A GPS receiver must have the correct signal levels to navigate Review Chapter 3 for information on connecting the STR4500 to a receiver and Section 5 2 4 for details of how to vary the signal levels using the power sliders If you are not sure
82. of the signal level required by your receiver then a logical progression follows Connect the receiver to the STR4500 front panel RF connector Runa simulation At this stage a static simulation is advisable Set the Power Adjustment sliders to Absolute mode and set all channels to 15 dB Most receivers have a signal level display either a bar graph or a signal noise S N figure for each satellite being tracked You should be familiar with typical values for real satellites and try to obtain similar values for simulated satellites by adjusting the power sliders accordingly If after 5 minutes at maximum power level no signals are being tracked or signals are being tracked intermittently at very low S N more power is required This may be the case when a receiver usually relies upon the additional RF gain provided by an active antenna You can correct for this shortfall in signal level in one of two ways Option 1 Increase the front panel output power via an RF amplifier Option 2 Use the rear panel Mon Cal output See Section 3 3 Having increased signal level using one of the options described above and with all the power sliders set to 15dB the receiver may begin to false lock False Locking is a phenomenon where satellites that are not currently being simulated are apparently tracked by the receiver possibly at low S N ratios If this occurs reduce all the power sliders until the receiver drops these false satellites and
83. orrection messages may be sent to a receiver via an available RS 232 port This is only valid when RTCM messages are included in the selected scenario and the receiver is RTCM capable STR4500 User Manual 49 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 6 2 RS 232 PORT SETTINGS The RS 232 ports must be configured before using the NMEA and RTCM facilities From the Menu Bar select Options gt RS 232 Port Settings R5237 Port Settings X Por com Settings Used by NMEA input Part come Settings Used by Not Used Apply Help Cancel g To set up an RS 232 port for use select the function NMEA in NMEA out or RTCM out to be associated with the port in the Used by field To set the port properties click the Settings button Check the receiver documentation for the correct settings typical settings for NMEA use are 4800 baud eight data bits no parity one stop bit Also determine if the receiver requires hardware or XON XOFF flow control and set the port appropriately For PCs with only one serial port set the Used by field for the second port to NOT USED These settings are stored and re used when the SimPLEX application is run again This does NOT affect the port settings used by other applications on the PC 50 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 6 3 SIMULATION DATA NMEA MESSAGES This option must be selected before the simulat
84. our first GPS simulation To stop the simulation click the STOP button The simulation stops and the current vehicle and satellite data display is held Click the Back to Start button to return to the start of the selected scenario and display the initial position data Click RUN to restart the simulation STR4500 User Manual 19 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 For more information on the software and its operation refer to the chapters that follow If you have not already done so and you wish to connect your GPS receiver at this point then refer to Section 3 3 You might also read Appendix 0 20 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 5 SOFTWARE REFERENCE MAIN FUNCTIONS 5 1 THE DEFAULT WINDOWS The default windows and their arrangement for an Aircraft scenario are shown in Chapter 1 5 1 1 VEHICLE DYNAMICS WINDOW The Vehicle Dynamics window displays vehicle data in a manner appropriate to the vehicle type the full screen in Chapter 1 showed the Aircraft display Displays for the other vehicle types are shown below For a car For a ship S 2 ej bl Vehicle Dynamics H ule zje Sl of laea l e SPEED Knots 30 0 Elevation 0 d Altitude m Vx m s Vy m s 1261x289 Vz m s Bank 0 Attitude geo heading elevation bank STR4500 User Manual 21 Spirent Communications Limited 2002 DGPO06
85. rt up POWER and HEALTH LEDs on the STR4500 front panel illuminate to show that everything is operating correctly If you want to run your first simulation without a GPS receiver connected skip to Chapter 3 3 3 CONNECTING YOUR GPS RECEIVER The signal input on a GPS receiver typically falls into one of three types 1 An input socket for a passive antenna 2 An input socket for an active antenna pre amplifier combination 3 A built in antenna only with no input connector some handheld receivers Determine which category your receiver fits and proceed as follows Type 1 Connect the receiver directly to the front panel RF OUTPUT connector using a suitable cable Type 2 Use an AC coupled amplifier with equivalent gain and noise figure to that used by the active antenna This amplifier can be 14 STR4500 User Manual Spirent Communications Limited 2002 1 07 Type 3 DGPOO603AAA powered either from an external power supply or from the receiver supply intended for the active antenna A bias tee DC block may be required as shown below Bias Tee STR4500 Receiver antenna port DC amp RF If this is not available an alternative is to use the high power MON CAL port at the rear of the signal generator As the signal is approximately 60dB larger than the front panel signal attenuation may need to be added As the noise floor for both the front and rear panel outputs is governed by the thermal noise of a coaxial
86. scription of the scenario You may add your own comments if you wish Defines the source files used in creating the scenario mainly for SPIRENT use Description of the GPS constellation and signal characteristics specification for the scenario SCEN TXT ASCII NAV_SAT TXT ASCII 1 antenna 1 vehicle 1 are filenames set at scenario generation time They allow for future expansion to multiple vehicle or multiple antenna simulations STR4500 User Manual 59 Spirent Communications Limited 2002 DGPOO603AAA 1 07 rE i PERSON TXT ASCII Description of the vehicle personality file Specifies the maximum dynamics for the vehicle antenna offsets and orientation etc Description of the SBAS constellation and signal characteristics specification for the scenario Only present if SBAS constellation included in scenario Description of the vehicle motion as a series of manoeuvres including climb turn etc SBAS_SAT TXT ASCII MOTION TXT ASCII Other files may be written to the scenario folder by the user when running the SimPLEX software gt 2 EE YUMA_ALM TXT ASCII v The GPS almanac used in generating this scenario See Appendix F 6 T File type Description gt 9 gt SIM_NMEA TXT ASCII v Simulation data in NMEA message format See Section 6 3 in subsequent simulations me pe P RA TXT a receiver See Section 6 4 RTCA TXT ASCII 4 Simulated RTCA messages in readable form See Sec
87. signal arrival angle is calculated in terms of the antenna pattern azimuth and elevation and attenuation is evaluated from the table above This figure modifies the signal level In summary the FINAL SIGNAL LEVEL BASE SIGNAL LEVEL modified by distance if MODELLED mode TX ANTENNA Attenuation if modelled RX ANTENNA attenuation The important point to note at last is that the RX antenna attenuation is not added at scenario generation time Instead an antenna attenuation array and signal arrival angles azimuth and elevation for each time step in the scenario are passed to the PC This means that the user may modify or replace the antenna pattern to modify the signal levels during a simulation The following section describes how this may be achieved E 2 MODIFYING REPLACING THE RX ANTENNA ATTENUATION PATTERN Each simulation will have an antenna pattern file named typically viatpat1 csv Vehicle 1 antenna 1 pattern 1 This is an ASCII Comma Separated Variable CSV file and is a 72 x 36 element array of gain values as described in the previous section The simplest pattern is one where all elements are set to OdB This will have no effect at all on any signal levels If we were to replace this with an antenna pattern where the attenuation for all ve elevation elements top half of array was O and for all ve elevation elements bottom half of array was 40 we would be specifying a hemispherical pattern Any GPS signals arriving
88. t Programs gt Accessories gt Command Prompt 84 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA Use the CD command to change to the directory to which you want to copy files then proceed as in the example below User input is displayed bolded The numbers in parentheses at the end of lines refer to the comments after the listing and should NOT be typed C temp2 gt ftp 192 200 1 204 1 Connected to 192 200 1 204 220 alpser FTP Server Version 4 2 Ready User 192 200 1 204 none gpssim 2 331 Username GPSSIM requires a Password Password xx xx 3 220 User Logged in ftp gt dir gpssim 4500 data myscen 4 200 PORT command successful 150 Opening data connection for DRAOI GPSS2M 4500 DATA MYSCENI 192620001 15 1652 Directory DKA0 GPS51M 4500 DATA MYSCEN TXT 3 9 9 FEB 2000 13 30 49 GPSSIM RWED RWED RE MYSCENs ZILP 1898 1899 9 FEB 2000 13 30 44 GPSSIM RWED RWED RE Total Of 2 tales 1901 190 BLOCKS 226 LIST Directory transfer complete ftp 326 bytes received in 0 05Seconds 6 52Kbytes sec ftp gt get gpssim 4500 data myscen txt 5 200 PORT command successful 150 Opening data connection for DKAO GPSSIM 4500 DATA MYSCEN TAT 1 192 200 1 15 1653 226 Transfer complete ftp 1313 bytes received in 0 00Seconds 1313000 00Kbytes se ec ftp gt binary 6 200 TYPE set to IMAGE ftp gt get gpssim 4500_data myscen zip 7 200 PORT co
89. t to a GPS receiver if the selected scenario includes correction messages Described in Section 6 5 5 4 3 10 User Actions File User actions may be recorded to a file and played back during subsequent simulations User actions that may be recorded are Signal On Off Power level adjustments and pseudorange ramps Select User Actions File from the Options menu on the menu bar before starting a simulation to display the following User Actions File Options Xx Scenario control actions Le power level adjustments and satellite ramp commands can be stored to a user actions file This file can then be replayed in subsequent runs Store actions to the following file Browse Replay the following file D Gosis TR4A500 4500_scenaroas scenl ramp_at_10_secs act Browse W Replay 2 see cma Normally the user would either select an existing set of actions to be replayed with the current scenario or select a new file to store any user actions performed when the scenario is run although it is possible to select both The buttons to the right of the screen open a browser window allowing a folder and file to be created or selected STR4500 User Manual 43 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 At the end of a simulation run where actions have been recorded a screen is displayed allowing the user to store or discard them Again browse buttons are provided at the right side of the screen to allow s
90. tFTP v 1 0 1998 2000 by Mike Walter ioj x ETP Script Commands View Tools Favorites Window Help S BrO so QHG Q S Hlm URL g 192 200 1 248 E Login gpssim Password Port 21 Anonymous Then click on the Connect icon the first icon in the row at the top of the screen This should connect to the Alpha and display the contents of the GPSSIM directory structure SmartFTP v 1 0 1998 2000 by Mike Walter ioj x ETP Script Commands View Tools Favorites Window Help BRO G e QNG Q 3 H a2 S05 7 URL SYSDEVICE GPSSIM E Login gpssim Password Potl2 Anonymous a 192 200 1 248 d SYS SYSDEVICE 3 GPSSIM E 21 03 00 10 57 CI 4500_DATA 04 11 99 14 48 BACK DATA DEFS DT E JOHN NETSCAPE amp PCDATA amp PGC RESULTS E SCRATCH 9 TEMP_BU 3 TAPE_TEMP 08 10 99 15 0 08 08 00 08 52 08 10 99 15 10 23 03 00 11 06 02 11 99 15 16 16 05 00 10 39 16 01 00 13 4 06 10 99 15 08 08 10 99 15 0 06 10 99 15 08 08 10 99 15 08 TAPE_TEMP 1HZ_BANK_ROLL CSV 239KB 16 05 00 13 34 H TEMP_BU a 1HZ_BANK_ROLL JOU Obytes 09 06 00 14 24 229KB 09 06 00 17 22 250KB 09 06 00 17 32 10 5KB 16 05 00 13 50 512bytes 18 08 00 10 57 300KB 19 07 0010 33 PORT 192 200 1 15 4 12 PORT command successful Opening data connection IP 192 200 1 15 PORT 1036 LIST Opening data connection for SYSSSYSDEVICE GPSSIM 192 200 1 15 103
91. tallation is required See Appendix J Note that under Windows 2000 and Windows xP different accounts with different privileges may be set up The PC supplied is configured with two accounts administrator password admin the administrator system manager account and gpssim password nicola a Standard User type account in the group gpsusers You should log in to this account on starting the PC to run the SimPLEX software A CD to re install the appropriate operating system is supplied with the PC In the event of a software upgrade see Appendix J for information regarding re installation of the SimPLEX software 12 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 3 CONNECTING THE SYSTEM 3 1 SAFETY NOTICE Product Safety Information Sheets PRODUCT TITLE PRODUCT CODE DATA SHEET No GPS SBAS SIMULATOR STR 4500 N A PRODUCT SAFETY INFORMATION SHEET This safety Information Sheet should be read in conjunction with the Product Data Sheet where applicable Failure to observe the ratings and the information on this sheet may result in a safety hazard This PSIS applies to the signal generator unit of the simulator only For information on the computer workstation see safety section of the manufacturer s handbook 1 MATERIAL CONTENT This unit contains Printed Circuit Board semi conductor assemblies Materials contained within the unit include PT
92. te DCR 121 NMEA timing diagram 1 07 Oct 2002 Update to SPIRENT contact information and Signal Generator performance specifications References to SIMGEN and SimGEN For VMS software suites SimPLEX support under Windows XP 2 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA TABLE OF CONTENTS 1 HITROGI CUO eaei a E O E N T 1 1 Referenced Documents se sneha a cee S acer 8 2 SUPPEA EMS torrioni E detadetecpatenseeiaaiecwacs 9 2 1 ITEMS LIS Piae a e e 9 2 2 STR4500 Simulator Indicators and ConnectorS ccceecee 9 2 2 1 ESTI We aS ASEEN EA EEN E E EE A 10 2 2 2 RECARE I G l hiatu E E OA 11 2 3 PC and Supplied Software t 22 cie do eee Meee ss 12 3 Connecting The System cccccccecceesseeeeeeeeeeeeseeeeseeeeeeesaeeeeeeas 13 3 1 Sale NOCO pyrina a a 13 3 2 System Interconnections cccsssccccssseeeceeeeeeceseeecseeseeesseeeeeees 14 3 3 Connecting Your GPS ReC IVED ccccccsseeeeceeseeeseeseeesseeeeees 14 4 Running Your First Simulation ccccceccceseeeeeeeeeeeeeeaeeeeeeeeees 17 5 Software Reference Main Functions ccccccceeeeeeeseeeeeeeees 21 5 1 The Default VViNGOWS 2 25 setsas Seo5 se iether ts ae a see tak aioe 21 5 1 1 Vehicle Dynamics WINdOW cc ccccssseccssseeseseeeseueeeneeeenenenens 21 5 1 2 Ground Track WindOW si csacie oa BA ease ieaited 23 51 3 SKV PIGUNVINGOW daea i a a E a asta 25 5 1 4 Power Levels WINdOW
93. tenna Pattern Window Two windows are displayed one showing the antenna pattern as a 3 dimensional polar plot the other as a 3D Cartesian plot effectively a graphical representation of the CSV file array Both representations may be viewed from different angles by using the sliders on the right side and bottom of the windows To modify the antenna pattern go to the menu bar and select Tools gt Antenna Pattern Editor to display the following screen im Ylalpatl csv Antenna Pattern Editor Ele Edit View Ee Hee ar a a a ay a H aa a FS eee eee Panola uefa ames oat MG el aaa ae 23 foo foo foo foo foo l l ea View _ on nm rm NIN TN TS nian T Miror p p p p L LEELLLEEEEL E Top Left Right ii Bottom o ing i i Undo All Undo Last r s oo o0 SS ao 407 eo p60 ao 80 100 700 720 120 140 140 760 760 780 180 200 200 220 annie EREHE wo 20 280 280 320 320 320 320 F oso sao T aso aso aso 200 20 20 260 oo N n 320 320 320 FT PHT AE F340 0 260 0 30 320 360 30 eee Poo PRE 40 reo peo 100 720 piao 760 EEJ 200 220 240 260 280 320 aT ow N a i N in Q fagi o gel ECEEE CEEEEL For Help press F1 The editor lets you set the value of each element of the antenna patt
94. the selected area Double clicking the left mouse button on this window displays the Position Details window See Section 5 2 1 The Position Details window may also be selected via the Menu Bar View gt Position Window or via the Tool Bar 24 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 9 1 3 SKY PLOT WINDOW The Sky Plot window shows the positions in the sky of the currently simulated satellites relative to the current vehicle position Each satellite position is denoted by a with its SVID adjacent As a satellite moves across the sky its track is plotted on the display Note This display does not change as a result of vehicle attitude changes 2 Sky Plot Satellites in View Set Ramp Cancel Ramp A satellite which is directly overhead 90 elevation will be shown at the centre of the display A satellite at 0 elevation will be on the circumference For vehicles at high altitudes it is possible that GPS satellites with negative elevations will be visible These satellites are STR4500 User Manual 25 Spirent Communications Limited 2002 DGPO0603AAA 1 07 denoted by an x symbol rather than a and their actual elevation is the negative of the elevation displayed The xDOP Dilution of Precision field provides an indication of the navigational accuracy obtainable by the receiver from the currently simulated satellite geometry
95. the software in the folder C Program files Spirent Communications SimPLEX and sets up a scenario folder structure C Program files Spirent Communications SimPLEX Scenarios Example scenarios named Example_Scenario1 sim and Example Scenario2 SIM are installed in the folders Scenarios Example_Scenario1 and Scenarios Example_Scenario2 respectively J 2 INSTALLING SIMPLEX OVER A PREVIOUS STR4500 INSTALLATION If you have an existing STR4500 software installation on your PC the SimPLEX setup program will detect this and offer the options to either Modify Repair or Remove the existing software It should be noted that users upgrading to SimPLEX software via the CD rather than a download from SPIRENT support website have the advantage that the CD contains the set of standard scenario files with updated simulation start dates of November 2001 STR4500 User Manual 109 Spirent Communications Limited 2002 DGPOO603AAA 1 07 If you wish to use these revised scenarios instead of the ones currently installed you are recommended to select the Remove option The Setup will delete all files installed by the previous Setup but will leave any files you have added subsequently including Log files and any Web Download Scenarios Then when the removal is complete Re start the SimPLEX Setup program to install the new software and scenarios If you wish to retain the original STR4500 scenarios with the earlier dates we recommend
96. tion 6 5 Filenames excluding extension may be specified by the user 60 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA 8 SOFTWARE REFERENCE REMOTE COMMAND SETTINGS This section details how the SimPLEX software may be controlled remotely from a user program or command file The command syntax is common to all inputs and is described first Then the various interfaces are described A remote command source is selected via the Options drop down See section 5 4 3 which presents the following display Remote Command Settings x MV Start remote task manually Remote commands can be obtained from a data file over an IEEE bus or from a R5232 serial port RS232 l Enable Data file user actions l Enable Bead Messages fot tie Tallon lEEE bus l Enable Receive messages ove BSD sockets Enable cont Tick the Enable remote input box to activate remote control and tick one of the sources and complete the associated items to enable that source STR4500 User Manual 61 Spirent Communications Limited 2002 DGPO0603AAA 1 07 The Start remote task manually option should only be used with the Data file Uuser actions source where the remote control icon on the tool bar is then used to start reading the control file For all other remote sources the external program initiates control 8 1 REMOTE COMMAND
97. with a ve elevation would be unattenuated signals arriving with a ve elevation with respect to the antenna would be severely attenuated This might be used to model an antenna mounted on the top of an aircraft wing where the wing would obscure satellites with a negative elevation Note that as the aircraft banks into a turn the wing may now obscure GPS satellites at certain positions and this will be fully modelled in the simulation If the user has characterised the gain for a specific antenna mounted on a specific vehicle this data may be entered as a CSV file and inserted into any scenario this is a powerful simulation feature STR4500 User Manual 93 Spirent Communications Limited 2002 DGPOO0603AAA 1 07 The software provides several ways to modify or produce CSV antenna files a Read the original CSV file into a spreadsheet that handles CSV files and modify it using the spreadsheet facilities b Read the original CSV file into a text editor and edit it manually This is not a preferred option as it would be very easy to lose a comma hence distorting the array c The SimPLEX software provides a utility to view and modify antenna pattern files as described in section E 3 94 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA E 3 VIEWING MODIFYING THE RX ANTENNA GAIN PATTERN To view the antenna pattern for the currently selected scenario go to the Menu Bar then select View gt An
98. you use the following procedure 1 Before you run the SimPLEX Setup Move the Scenarios folder to different directory e g Windows temp 2 Start the SimPLEX Setup and where prompted select the Remove Option 3 Re start the SimPLEX Setup and Select the Custom Install Option 4 Ensure that all Scenario install options are deselected and continue with the Installation 5 Finally Move your saved Scenarios Folder from the temporary location to the SimPLEX folder to overwrite the new and empty SimPLEX Scenarios folder If you wish to have available both sets of scenarios old and new dates we advise you to repeat the above procedure but this time do install the new scenarios On completion of the installation create a new folder called SimPLEX Old Scenarios and copy the old scenarios in 110 STR4500 User Manual Spirent Communications Limited 2002 1 07 DGPOO603AAA K STR4500 TECHNICAL SPECIFICATION The full product specification is SPIRENT document MS2980 the following are extracts from this document K 1 SIGNAL GENERATOR CONNECTIVITY PORT Primary RF OUT COAXIAL Type N Female COAXIAL Type SMA Female External Reference INT REF OUT Internal Reference Oscillator 1PPS OUT COAXIAL BNC Socket OUT COAXIAL TTL level compatible 1 pulse per BNC Nominal width 100ms aa Socket 50 ohm 1 DC isolation can withstand a maximum DC level of 100V and reverse RF levels to a maximum of 1W STR4500

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