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1. dg Agilent Technologies Advanced Design System 1 5 Bluetooth DesignGuide March 2001 Notice The information contained in this document is subject to change without notice Agilent Technologies makes no warranty of any kind with regard to this material including but not limited to the implied warranties of merchantability and fitness for a particular purpose Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing performance or use of this material Warranty A copy of the specific warranty terms that apply to this software product is available upon request from your Agilent Technologies representative Restricted Rights Legend Use duplication or disclosure by the U S Government is subject to restrictions as set forth in subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause at DFARS 252 227 7013 for DoD agencies and subparagraphs c 1 and c 2 of the Commercial Computer Software Restricted Rights clause at FAR 52 227 19 for other agencies Agilent Technologies 395 Page Mill Road Palo Alto CA 94304 U S A Copyright 2001 Agilent Technologies All Rights Reserved Bluetooth DesignGuide 1 Bluetooth DesignGuide QuickStart Using the DesignGuide c cccccceeecceeeeeeceeeeeeceneeesaeeseeeecaeeseaeeseeeeeeeseaeesseeneeeees 1 2 The DesignGuide Menu 2 ccccccceeceeeee2. delay can be specified in microseconds Each tap coefficient has a Rayleigh power distribution and a uniform phase distribution For a specified value of time T burst the channel snapshot is kept fixed For the next Tburst duration a new channel snapshot is taken The tap coefficients for each snapshot are available The corresponding values of the RMS delay spread and the mean excess delay are also available TK plots for these measurements can also be enabled The tap coefficients are calculated by r exp Dday Tap Mean_Dday a0 1 Mean_DeayDday Tap al r a0 a2 r al an r a n 1 Multipath Propagation Test Benches 2 13 Bluetooth DesignGuide Reference BER Outage w MPath Noise No Chan Filter TEST_MULTIPATH_BER_NOFILT Summary This test bench calculates the BER without a channel filter but with multipath included It will usually exhibit ideal BER because the C N is large the transmit power is 0 dBm and no noise is included The mean delay is larger than for the other Multipath test benches being set to 0 2 usec and the tap delay is 0 05 usec To observed channel outage activate SweepSeed to vary the random seed value used by the Data Flow simulator A channel with BER gt 0 1 is considered to have caused a failed burst transmission The simulation time is about 120 seconds with ParameterSweeps deactivated for 250 bits using a PI 11 650 MHz under NT with 256 MB RAM Thesimulation time will significantly increase
3. particular channel snapshot It shows the eye diagram the channel snapshot the recovered and transmitted bits the BER and the RMS delay spread For channel outage simulations only the BER should be enabled and the seed and or frequency varied over a large number of points TEST_MULTIPATH_BER_AWGN This performs simulations similar to that in TEST_MULTIPATH_BER but it also includes additive white Gaussian channel noise The input signal power level to an ideal receiver 0 dB noise figure can be set It shows the BER for both channel noise and multi path For channel outage simulations only the BER should be a enabled along with the channel power measurement if required For an example see display TEST_MULTIPATH_BER_AWGN 100 ns delay spread simulation for channel 2 20 Catalog of Test Benches and Subnetworks outage in which the signal power was set 3 dB above the 1 sensitivity level AWGN case without multipath TEST_MULTIPATH_BER_NOFILT This performs simulations similar to that in TEST_MULTIPATH_BER but the channel filter is not included In therefore shows the ideal BER underlarge signal to noise conditions System Compliance Tests TEST_RECEIVER_ADJ dsn The receiver adjacent channel rejection can be simulated in this test bench The rejection at alternate channel frequency the image frequency and the alternate channel to image frequency are the interesting points for the simulation TEST_RECEIVER_CCR dsn The co channel
4. 2 18 SubnetWorkS rrrrrrnvrrrnnnvrrnrnnvrrrnnnvrersnnverrnnnnersnnnnrrsnnvennsnnnersnnnnrrsnnnnnnnnnnnnsnnnnsnnnnn 2 22 Chapter 1 Bluetooth DesignGuide QuickStart The Bluetooth QuickStart Guide provides an introduction to the content and use of the Bluetooth DesignGuide It contains e A brief description e Section on using the DesignGuide e Section on displaying simulation data For detailed reference information refer to Chapter 2 Bluetooth DesignGuide Reference The Bluetooth DesignGuide is an application package for the Agilent Advanced Design System ADS which contains various system test benches and reference designs for example an optimal low I F receiver for the RF portion of the Bluetooth physical layer Briefly it allows for the investigation of system performance from simple EYE diagrams to BER the ultimate test when there are present impairments such as AWGN Gaussian noise VCO phase noise multipath and or co channel adjacent channel intermodulation pulsed RF interference In many cases the receiver s EYE diagram may be observed in real time during the simulation while the level of the signal or interferer is adjusted via an interactive slider In addition the DesignGuide addresses some PLL VCO design issues and hel ps you select the best demodulator for your receiver All of these applications are easily accessed via a menu type user interface that is integrated with ADS when the DesignGuide is insta
5. 200 usec To understand how to optimize the loop filter select VCO Parameter Optimization HV m VCO DivideByN V DC ee VCO3 SRCA l Ydc 0 5 Y Vhigh 1 V den cal Vlow 1 V FO Fyco Hz N Ndiv N Rout 50 Ohm IIH Powerdbmtow 0 Delay 50 nsec Where Do I Start 2 7 Bluetooth DesignGuide Reference Synthesizer Step Response 2 60 2 55 2 50 fvco V 2 45 2 40 0 20 40 60 80 100 time usec 2 8 Where Do I Start Component Subnetwork Evaluations Following are details on designs demonstrating component subnetwork evaluations Channel Filter Impulse Response TEST_FILTER_IMPULSE dsn Summary This test bench evaluates the impulse response of the Bessel filter used for pulse shaping in the Bluetooth Receiver ADS has twomain simulation modes Analog RF and DSP This Test Bench compares the impulse responses of the circuit A RF and timed DSP models which can be very similar The A RF model has an advantage in that its group delay at the edge of the passband may be controlled However using it in a DSP design requires Transient cosimulation which may be slower Channel Filter Swept Response TEST_FILTER_COMPLEX dsn Summary This test bench sweeps the complex receive filter model used in the Design Guide FILTER CHEB COMPLEX Open Data Display TEST FILTER COMPLEX Note that the QAM Demod is set for a Gain I mbalance of 0 5 dB and a Phase I mbalance of 3 degrees The data display compares the sw
6. ER Bit Error Rate calculations additional Data Displays are available Access them by selecting the Display options listed under the test bench item on the menu after the test bench has been opened Displaying Simulation Data 1 3 Bluetooth DesignGuide QuickStart Interactive Simulations Some of the simulations that use Tk displays also have interactive sliders that allow a parameter to be adjusted during the simulation so the results can be immediately observed When you want to run a non interactive simulation so that output data are only collected by sinks such as time domain or spectrum measurements all Tk items should be de activated The subnetwork TkPowerControl should also be de activated and bypassed with a wire because it contains an interactive slider Test EYE Sensitvity IIIS 2 iol m senn BEE D DesignGuide Help Test EYE Sensitivity Ea en O A al Ne WEE i T T T T 1 14 4 evel dBm el YES Clock Recovery out p CLOCK RECOVERY HP Ptolemy Control Panel BEE I Continue Quit Power Level dBm 70 0 Scale 0 3161 0 00 1 87 3 73 5 60 747 Signal Power Atten dB x 10 0011887268767 Interactive Slider 1 4 Displaying Simulation Data Chapter 2 Bluetooth DesignGuide Reference The Bluetooth DesignGuide User Manual contains application guidelines for using the test benches provided with the Bluetooth DesignGuide including Bas
7. EST_GAUSSIAN_FIR_FILTER shows the impulse response TEST_LOWIF_FILTER_DEMOD dsn This test bench is used for comparing and optimizing the combination of the channel filter along with various types of poly phase FM Demodulators TEST_LOWIF_FMDEMOD dsn This is similar to the TEST_LOWIF_FILTER_DEMOD dsn test bench The effect of a poly phase harmonic suppression band pass filter at the output of the hard limiters is investigated TEST_LOWIF_RECEIVER dsn This is similar to the TEST LOWIF_FILTER_DEMOD dsn test bench The complete receiver chain is investigated VCO PLL Phase Locked Loop Investigations TEST_PLL_SS dsn The RF synthesizer reference frequency spurs due to charge pump mismatch can be observed in this harmonic balance steady state simulation TEST_PLL_TR dsn The transient response of the RF synthesizer is simulated in this test bench TEST_PLL_TR_linear dsn This is the main test bench for optimizing the RF synthesizer parameters The loop filter components are defined in terms of 2 parameters z related to damping constant and fn related to loop band with The various results are shown in displays beginning with the name TEST_PLL_TR_linear Catalog of Test Benches and Subnetworks 2 19 Bluetooth DesignGuide Reference Multipath Propagation Test Benches TEST_MULTIPATH_ IMPULSE The impulse response of the multi path channel is simulated in this design The frequency response of the channel is obtained with and wi
8. MOD This puts additional requirements on the demodulator in exchange for a simpler signal path Component Subnetwork Evaluations 2 11 Bluetooth DesignGuide Reference Multipath Propagation Test Benches Following are summaries of test benches used for multipath propogation Multipath Impulse Response TEST_MULTIPATH_IMPULSE Summary This test bench evaluates the MULTIPATH_EXPONENTIAL model using an impulse input The delay spread profile is shown in the associated data display Due to the use of a moving average over 512 symbols the data display will require several minutes to open about 2 minutes for a P111 650 under Windows NT Select Display I mpulse Response after the schematic is displayed to show the data display window Note The Multipath subnetwork requires a large memory space due to its complexity Performance will be reduced on systems having less than 256 MB of RAM 2 12 Multipath Propagation Test Benches Impulse GainRF MULTIPATH_EXPONENTIAL n G1 x9 TStep Tstep usec Gain 10 16 20 Tburst Tstop FCarrier Frf MHz N_burst_save 1 Veight Tstop Tstep Y Tstep Tstep Period Tstop 2 usec frt Frt Delay 0 0 sec 0 4 0 3 wo g s 0 2 N 0 1 0 0 0 2 4 6 3 10 12 14 16 18 20 Index Tap coefficients for one burst typical The Multipath_E xponential model implements an exponential power decay multi path channel model that is widely used for indoor propagation The mean excess delay and the tap
9. PN FMMOD plus an ideal FM modulator Top level parameters include the phase noise level and Q RECEIVER dsn The Bluetooth receiver has a front end low noise amplifier that models the noise figure and the third order intercept point It is followed by a quadrature amplitude demodulator that indudes the phase and gain imbalance The local oscillator for this demodulator down converter includes the phase noise The output of the quadrature amplitude demodulator is a 1 MHz low IF complex signal comprising the in phase and quadrature phase signals These signals are high pass filtered to remove DC offsets due to local oscillator self mixing and to remove time varying DC offsets as a result of second order non linearity effects on out of band pulsed jammers After the high pass filters there is a complex channel filter with quadrature inputs and outputs This filter is centered at 1 MHz and has an asymmetric positive and negative frequency response The quadrature outputs of the Catalog of Test Benches and Subnetworks 2 23 Bluetooth DesignGuide Reference channel filter are hard limited and then de M odulated by a complex FM demodulator This FM demodulator can be implemented in various ways The preferred Solution is to have a complex Bessel filter that implements a delay with the delay signals cross multiplied with the inputs signals and then summed at the output The combination of the complex channel filter and this Bessel filter have to be careful
10. _DATA is input to an ideal ADS FM modulator component The TkPowerControl follows which allows the signal level to be adjusted using an interactive slider The AWGN CHANNEL adds thermal noise equal to 174 dBm Hz to the signal AWGN Channel g r AWGN CHANNEL FM Mod TkPowerControl x2 F3 Ro x FCarrier Frf MHz ControlName Signal Attenuation dB Power dbmtow Prx Sensitivity 2 dev The signal is bandpass filtered and ideally demodulated i ae DEM ae ae F hd a FM Demod p F2 FCenter Frf MHZ RIn 50 0 Ohm PassBandwidth 1 4 MHz PassRipple 0 2 N 5 ROut 50 0 Ohm RTemp 273 15 RefFreq Frf MHz Sensitivity 1 dev Phase 0 0 2 4 Where Do I Start Demod if 2 DJP EJOJA 7 d alila g IN sl ove Continue Quit Power Level dBm 70 0 Scale 0 3161 10 0011887268767 TimedToFloat Ti TkPlot 12 0 00 1 97 3 94 5 92 7 89 Interactive slider After scaling and conversion to floating point the EYE diagram is displayed on a TkPlot In this simulation SHAPED_DATA TkPowerControl and AWGN_Channel are subnetworks created for the Bluetooth DesignGuide Where Do I Start 2 5 Bluetooth DesignGuide Reference Transmit Spectrum TEST_TX_SPECTRUM dsn Summary This test bench is intended to illustrate some of the filtering options for the Bluetooth transmitter When the 8 bit FIR filter is used images of the spectrum
11. are seen at intervals related to the sampling rate H owever these images are below the phase noise sidebands and are hence adequately filtered out Additional analysis of the FIR filter may be found by selecting Component Subnetwork E valuations gt Transmit Filter Gaussian FIR Transmit Spectra using Ideal 8 bit FIR and FIR Filter w Phase Noise Images due to FHR Filter SFR S_IDEAL S_FIR_PN 2360 2365 2370 2375 2380 2385 2390 2395 2400 2405 2410 2415 2420 2425 2430 2435 2440 2 6 Where Do I Start VCO PLL Phase Locked Loop Investigations In this category of Test Benches a set of tools are provided to assist in the design and optimization of signal sources for a Bluetooth implementation These are intended as basic tools that address some key performance requirements For help with the full PLL design flow the PLL DesignGuide for ADS is available VCO Response to Frequency Step TEST_PLL_TR This test bench demonstrates Bluetooth Fractional N Synthesizer transient response to an 80 MHz step The VCO frequency is 2 4 GHz and the Reference frequency is 1 MHz The output frequency is F vco N or 2 48 GHz The loop bandwidth fn is 5 kHz This design which is simulated under the Transient controller uses the VCO_DivideByN and PhaseF reqDet components The PFD output is coupled to the RC loop filter using the Voltage Controlled Current Source VCCS The frequency of the source must settle to within H 20PPM in
12. e receiver This sub network extracts the bit timing from an initial stream of data and then freezes the recovered block phase after Ntrainer_sym bits It also samples the de M odulated bits at the middle point of each bit using the recovered clock DEMFM OHZ dsn A zero IF poly phase FM demodulator including a down converter from low I F zero 1 F DEMFM BESS MULT dsn A delay and multiply poly phase FM demodulator The delay is implemented using a Bessel filter This novel method provides exceptional performance when compared to the other demodulators DEMFM_DAMCKT dsn A differentiate and multiply poly phase FM demodulator at the A RF circuit level DEMFM DELAY MULT dsn A system level delay and multiply poly phase FM demodulator DEMFM IQDIGITAL dsn A poly phase digital FM demodulator FILT_HP_50KHZ N1 dsn First order high pass filter generated from the DSP filter designer in ADS It is used in the RECEIVER to remove DC following down conversion FILT_LP_N1 dsn First order low pass filter FILTER BESSEL COMPLEX dsn Poly phase band pass filter with Bessel response FILTER BESSELckt dsn Circuit level Analog RF sub network used in FILTER BESSELckt COMPLEX dsn FILTER BESSELckt COMPLEX dsn Complex filter sub network used in DEMFM BESS MULT FILTER CHEB COMPLEX dsn Complex filter sub network used as a channel filter in theRECEIVER 2 22 Catalog of Test Benches and Subnetworks MIXER_COMPLEX dsn Complex mixer used in t
13. eeeeeeceeeeeeeeeeaeeeaeeceaeeseaeeseeeeeeeeeseeeesaeesaes 1 3 Displaying Simulation Data servvrnnnnnrnnnonvrnnennvrnnrnnrrnnenvrnnnnnvrnnnenvrnnennvensennrnnsrnnnnnenn 1 3 Interactive Simulations rennnnrnnrnnrnrrnrn nn nnnn ner rann venn nnnnnnnnnnnnrnnnnrnnnnnnnennnnnnn 1 4 Bluetooth DesignGuide Reference Where D l Start moenia aaraa ae ETANO die anestesi 2 2 Basic System Test Benches rrnnnnnnnnnrnrnnrnvnnnnnnrnnnnrnnnnrnnnnnnnennnnnrnnnnrnnnrnnnennnnenn 2 3 VCO PLL Phase Locked Loop Investigations mrnnrnrnrrrnrrrrnrnrrnrnrrnnnrnnnnnnn 2 7 Component Subnetwork Evaluations cc cccecceeeceeeeeceeeeeeeeeeeeeeeaeeseneeeseeteaeeeeaees 2 9 Channel Filter Impulse Response TEST FILTER IMPULSE dsn 005 2 9 Channel Filter Swept Response TEST_FILTER_COMPLEX dsn 0 0005 2 9 FM Demodulator Selection TEST LOWIF FMDEMOD rrnrnrrnvnnrnrnnnnnrrnnnnrn 2 10 Multipath Propagation Test Benches sanrrnnannvrnnnnnrrnnenvrnnnnnvrnnnenvrnnennvensennrnnsrnnnnnenn 2 12 Multipath Impulse Response TEST MULTIPATH IMPULSE J mrrnnrrvernnvvrrrnnnr 2 12 BER Outage w MPath Noise No Chan Filter TEST MULTIPATH BER NOFILT 2 14 System Compliance Tests cc ccceccecececeeeeeeeceeeceeeeeecaeeecaeeseneesaeeeeaeeeeneeseeeeeneeesaees 2 16 Catalog of Test Benches and Subnetworks ccccccecceeeeeeeceeeeeeeeeeeeeeeeeeeeesneeesaees 2 18 Test Benches uante auna ananasen He A EEE E TE
14. ept RF response to the balanced condition Component Subnetwork Evaluations 2 9 Bluetooth DesignGuide Reference 10 10 Gain Imbalance 0 5dB Phase Imbalance 3 de Gain Phase Imbalance 0 FM Demodulator Selection TEST_LOWIF_FMDEMOD Summary An EYE diagram display allows for the relative performance of various demodulators to be observed Due to the different output levels and the amount of residual DC for each demodulator select View gt View ALL on the Demod_TEST TkPlot to see the EYE diagram 2 10 Component Subnetwork Evaluations Demodulator selection is important when designing a Bluetooth solution because receiver performance is often largely dependent upon the demodulator s performance The DesignGuide provides a choice of several demodulators Activate one demodulator at a time Push into each subnetwork to see it s structure h FM Demedi mee Bessel Id iplier Demod IDEAL Demod TEST DEMFM BESS MULT x4 Fif Fif x5 0 i 106 4 Damo D 00 dier Descriptions of each demodulator are available in the Catalog of subnetworks The DEMFM_BESS_MULT is notable for excellent performance An additional test bench available under FM Demod Sdection w Channd Filter uses just a single complex Chebyshev channel filter in the receiver instead of the high pass Chebyshev limiter Bessel signal path used in TEST_LOWIF_FMDE
15. he system level implementation of poly phase bandpass filters MULTIPATH_EXPONENTIAL This design implements an exponential power decay multi path channel model that is widely used for indoor propagation The mean excess delay and the tap delay can be specified in microseconds Each tap coefficient has a Rayleigh power distribution and a uniform phase distribution For a specified value of time T burst the channel snapshot is kept fixed For the next Tburst duration a new channel snapshot is taken The tap coefficients for each snapshot is available The corresponding values of the RMS delay spread and the mean excess delay are also available TK plots for these measurements can also be enabled MULT_RF_BB dsn Subnetwork used in MULTIPATH EXPONENTIAL MULTIPATH_TAP_C dsn Sub network used in MULTIPATH_EXPONENTIAL to generate random noise and phase characteristics according to the exponential tap coefficients OSC_PN dsn System level RF oscillator with phase noise OSC_PN_FMMOD dsn Baseband phase noise generator use as modulation input voltage to an FM modulator PLL_TR_linear dsn Used in TEST PLL NOISE and TEST PLL TR linear POWER dsn Output is a signal that has a value equal to the input signal power in dBm It is useful in evaluating the effect of multipath fading POWER GATED dsn Time gated version of POWER dsn TRANSMITTER dsn The Transmitter is used in most of the Test Benches It is constructed using SHAPED DATA and OSC
16. ic System Test Benches e Component Subnetwork Evaluations e VCO PLL Phase Locked Loop Investigations e Multipath Propagation Test Benches e System Compliance Tests For a useful reference list refer to the section Catalog of Test Benches and Subnetworks on page 2 18 Note This manual assumes that you are familiar with all of the basic ADS program operations For additional information refer to the ADS User s Guide For access to the complete set of ADS online documents select Hap gt Topics and Index from an ADS program window 2 1 Bluetooth DesignGuide Reference Where Do I Start Your first steps depend on whether you are creating or integrating a design Designing a Bluetooth solution This DesignGuide provides a reference receiver design that can be evaluated against measurements of your RF hardware and simulations of an ADS model of that RF hardware There are also other tools that target specific components of the Bluetooth physical layer It is suggested that you review the Basic System Test Benches first followed by the Component Subnetwork E valuations emphasizing filter selection The VCO PLL segment may be useful if you are either designing a synthesized source or need to optimize an existing design for good time domain performance and phase noise characteristics Finally the System Compliance Tests focus on evaluating performance in the presence of interferers Integrating a Bluetooth solution For in
17. if less than 256 MB of RAM are available Rer Dan maang hose KA FM Mo Sr F3 eie EXPONENTIAL hy _Demod aii gt i FCarrier Frf MHz BitsPerSym 1 Tburst Tburst Ed 1idev ae _sym 45 Tsym Tsym Powersubrtow 0 N_burst_save 1 y Tsym Tsym BT BT Sensitivity dev 2 Tstep Tstep 2p Tstep SamplePerSym Sample trf Frt PARAMETER SWEEP Preamble 20 ParamSweep SweepSeed SweepVar seed SiminstanceName 1 DF1 SiminstanceName 2 SiminstanceName 3 SiminstanceName 4 SiminstanceName 5 SiminstanceName 6 Start 123456 Stop 1 23466 Step 1 2 14 Multipath Propagation Test Benches N mean excess delay l N rms delay l 0 213 0 191 T fmdemod Y o 8 a so en 70 ga so The preceding figure shows a portion of the output display for multipath 0 2 usec delay setting with no channel filter at the output of the ideal FM demodulator The Clock Recovery action must accept this distorted input and re synch the data It might be informative to vary this test bench by substituting other non ideal demodulators such as the subnetworks provided with the DesignGuide and observe their performance under multipath conditions Multipath Propagation Test Benches 2 15 Bluetooth DesignGuide Reference System Compliance Tests This category of test benches is intended to provide a convenient starting point for validating a Bluetooth system The tests are based on the Bluetooth Specificatio
18. lled Bluetooth DesignGuide QuickStart Using the DesignGuide The Bluetooth DesignGuide adds a menu selection to each ADS Schematic window under DesignGuides which provides convenient access to test benches subnetworks and data displays It may be installed by itself or may be installed along with other DesignGuides Bluetooth DesignGuide a QuickStart Guide CDMA2000 DesignGuide Basic System Test Benches Linearization DesignGuide gt Component Subnetwork Evaluations Mixer DesignGuide VCO Phase Locked Loop PLL Investigations gt Multipath Propagation Test Benches Oscillator DesignGuide Receiver Sensitivity System Compliance Tests Display BER Sweep User Manual Display Time Domain Response Toggle Quick Help About Bluetooth DesignGuide Tc IV Co Channel Interference Blocking Display Time Domain Response Display BER Sweep Adjacent Channel Interference Spectrum Adjacent Channel Interference Blocking Display Time Domain Response Display BER Sweep Combined Adjacent amp Co Channel Inteference Display BER Sweeps Intermodulation Compliance Test Display Time Domain Response Display BER Sweep Pulsed Interference w 2nd Order Intercept Display Time Domain Response Display BER Sweep 1 2 Using the DesignGuide The DesignGuide Menu All of the DesignGuide contents are accessed using the Bluetooth DesignGuide menu found under the DesignGuide pull down on any schematic windo
19. ly designed to produce the minimum distortion of the de M odulated signal The demodulator and signal have unwanted high frequency components that are removed by the following data filter Following the data filter is the data slicer that converts the analog demodulated signal into digital bits RECEIVER_IP2 dsn The effect of out of band pulsed jammers on the receiver sensitivity is modeled in the RECEIVER_IP2 design It is otherwise similar to RECEIVER dsn The pulsed jammers produce pulsed DC offsets in the baseband quadrature signal paths The relative power of the jammer and the co channel rejection of the receiver are the variables that can be set in the TEST RECEIVER 1P2 dsn top level simulation Based on this the required IP2 is computed and use in the top level BER simulation SHAPED_DATA This sub network implements both 2 and 4 level pulse shaping for GFSK modulation In addition a 10101010 preamble is inserted at the start of the simulation 2 24 Catalog of Test Benches and Subnetworks Index c component evaluations 2 9 D data displays 1 3 E eye diagram 2 3 F filtering options 2 6 M menu setup 1 3 multipath propogation 2 12 S signal source optimization 2 7 subnetwork evaluations 2 9 subnetwork list 2 18 system compliance tests 2 16 T test benches basic 2 3 test benches list 2 18 Index 1
20. n version 1 0 B Radio Specification Section 4 Receiver Characteristics and the RF Test Specification v 0 9r7 section on C I performance and are summarized in Table 2 1 Table 2 1 Interference Performance Requirements Wanted signal level Interferer Type Interferer level P dBc P dB gt reference sensitivity Co Channel interference C I 11 dB 10 Adjacent 1 MHz interference C I 0 dB 10 Adjacent 2 MHz interference C I 30 dB 10 Adjacent 1 MHz interference C I 40 dB 3 Each test bench sets up a starting condition according to Table 2 1 and other conditions might be easily specified For example the adjacent interferer offset can be set to 1 2 3 or more MHz away from the wanted signal An interactive slider provides for attenuating the interfering signal while observing the EYE diagram For BER tests the interactive slider is not used and the appropriate components are de activated as described on the test bench In addition to the Co Channel and Adjacent Channel tests the following are also available e Combined Co Channel Adjacent Channel test e Intermodulation test e Pulsed Interferer with 2nd order Intercept IP 2 Test Bench 2 16 System Compliance Tests From the Adjacent Channel I nterference Blocking Test Bench VAR an VARI acr 0 acr sets the interferer s relative power M 1 M sets the frequency offset in MHz kg Prx sets the wanted signal s p
21. nitial two level training sequence SLICER dsn This design extracts the average level of the analog de M odulated signal and uses this level as the slicing reference to a comparator input The incoming analog signal is sliced into digital bits by the comparator The slicer behavior is depicted in the display SLICER TEST_CHANNEL_FILTER dsn The combined behavior of the high pass DC notch filters and the complex channel filter is simulated in this design TEST FILTER COMPLEX dsn The complex channel filter behavior of his simulated in this design TEST_FILTER_COMPLEX_TIME dsn Thetime domain response of the complex channel filter is simulated here TEST_FILTER_IMPULSE dsn The impulse response of circuit level and system level low pass Bessel filters are compared in this simulation These low pass Bessel filters were used in the design of the band pass complex Bessel filter The system level 2 18 Catalog of Test Benches and Subnetworks mode of the filter was preferred to speed up the simulation However it had to have an impulse response that was identical to that of the circuit level filter model TEST_GAUSSIAN_FIR_FILTER dsn The Gaussian filter is implemented digitally as a 17 tap FIR filter with a the six bit word length for each tap The impulse response of the filter is simulated in this design The impulse response is saved into a file Data from this file is then used to define the tap coefficients of an FIR filter The display T
22. ower Bits 1000 Tslice 16 5 Ntrainer 65 HP Ptolemy Control Panel px Continue Quit Power Level dBm N 60 0 Interferer Relative Power dBm 0 0 Interferer Separation MHz 1 0 0 00 1 87 3 73 5 60 7 Scale 1 0 ADI Interferer 0 0 The preceding graphics show the EYE diagram and Control Panel for the Adjacent Channel Interference Test Bench Moving the slider to the left will attenuate the interferer level System Compliance Tests 2 17 Bluetooth DesignGuide Reference Catalog of Test Benches and Subnetworks Following are details on the available test benches and subnetworks Test Benches Following are details on the available test benches Basic System Test Benches TEST_TX_SPECTRUM dsn The spectrum of the transmitter can be simulated here The effects of phase noise and Gaussian filter quantization can be observed and checked against the allowed spectral template for various standards TEST_EYE dsn This is a quick simulation to observe the eye diagram due to the combined effects of the transmitter and the complete receiver TEST_TX_RX_EYE dsn The eye diagram corresponding to the detailed model full Transmitter and lowl F Receiver with phase noise and filters end to end link can be simulated in this design Component Subnetwork Evaluations SHAPED_DATA dsn This design models a two level or four level Gaussian filtered data source It includes an i
23. rejection of the receiver can be simulated here TEST_RECEIVER_TEST_INTERMOD dsn The effects of two tone jammers due to third order receiver non linearity and the reciprocal mixing of these jammers due to phase noise are simulated here TEST_RECEIVER_SENSITIVITY dsn The receiver sensitivity in an addictive white Gaussian noise channel at 174 dBm Hz is simulated in this design TEST RECEIVER IP2 dsn The effect of out of band pulsed jammers on the receiver sensitivity is modeled in the RECEIVER 1P2 design The pulsed jammers produce pulsed DC offsets in the baseband quadrature signal paths The relative power of the jammer and the co channel rejection of the receiver are the variables that can be set intheTEST RECEIVER 1P2 dsn top level simulation Based on this the required IP2 is computed and use in the top level BER simulation Catalog of Test Benches and Subnetworks 2 21 Bluetooth DesignGuide Reference Subnetworks AGC This block is used at the output of the MULTIPATH EXPONENTIAL block for setting the mean output power to a given fixed level instead of letting it vary with each channel snapshot It measures the mean power of the signal coming from the MULTIPATH_EXPONENTIAL block in a small time window after which it adjusts the gain in order to set the mean power at the design level AWGN CHANNEL dsn Models the Thermal Noise of an RF channel CLOCK_RECOVERY dsn Used for a bit timing recovery and sampling of sliced data in th
24. tegrating into a product such as another wireless device handset or any environment with other RF emitters the DesignGuide provides simulation based tools for understanding system performance under various conditions It is suggested that you review the Basic System Test Benches first followed by the System Compliance Tests The Multipath Propagation Test Benches add the ability to model certain indoor propagation conditions and observe the effect on the system s performance In the following sections some important Test Benches are discussed in detail 2 2 Where Do I Start Basic System Test Benches The basic system test benches provide an introduction to the Bluetooth RF interface Here we will use them to discuss in detail some of the main components and subnetworks used in the DesignGuide Ideal Transmit Receive EYE Diagram TEST_EYE dsn This is a quick simulation to observe the eye diagram due to the combined effects of the transmitter and the complete receiver This system is built from only the most basic components starting with SHAPED_DATA This component produces Gaussian filtered MSK data according to the Bluetooth specification An optional Preamble which consists of the 10101010 sequence may be included by setting Preamble gt 1 SHAPED_DATA X1 BitsPerSym BitsPerSym Tsym Tsym BT BT SamplePerSym Sample Preamble 1 Where Do I Start 2 3 Bluetooth DesignGuide Reference The output of SHAPED
25. thout averaging done over any given modulation bandwidth e g 1 MHz for Bluetooth The results are shown in the display TEST MULTIPATH IMPULSE At frequencies where there is a large relative channel loss without averaging one can expect severe intersymbol interference due to multi path It can also be seen that the correlation bandwidth is approximately the inverse of the RMS delay spread TEST_MULTIPATH_POWER Varies the channel snapshot and measures the corresponding Modulated signal average power at the output of the channel The corresponding RMS delay spread values are also available The display TEST MULTIPATH POWER 200 50 seed shows the simulation results for a 200 ns delay spread using tap spacing of 50 ns A large number of channel snapshots were taken for the simulation The pdf and cdf distributions of the multi path loss are also shown TEST_MULTIPATH_EYE This shows the TK plot of the FM de Modulated eye diagram under multi path conditions The corresponding multi path tap coefficients and RMS delay spread values are also shown TEST_MULTIPATH_ EXPONENTIAL This simulation shows the variations in both the mean power and the instantaneous Modulated power for various channel snapshots along with the corresponding delay spreads TEST_MULTIPATH_BER This simulation measures the BER for various channel snapshots It is useful for computing the channel outage when the signal to noise ratio is large See display TEST MULTIPATH BER for one
26. w The contents have been divided into several categories Basic System Test Benches Tutorial simulations to help you understand the Bluetooth RF segment and to evaluate some filtering options for the transmitter Component Subnetwork Evaluations Simulations to help you understand and validate many of the built in subnetworks used in the system test benches VCO Phase Locked Loop PLL Investigations Simulations of PLL topologies which address timing and noise issues Multipath Propagation Test Benches Simulations that include multipath models for investigating system performance under non ideal indoor propagation conditions System Compliance Tests System test benches for sensitivity and blocking performance From each category move the cursor to the right to open the menu that displays the available items Each selection except those named Display will open a top level test bench schematic and in many cases a data display will also open The Display selections will open additional data displays but only after the test bench listed above it has been opened There are also menu selections to open this QuickStart help a User Manual and an About box Displaying Simulation Data Some test benches have real time Tk displays that open by themselves each time a simulation is performed Other test benches will automatically open a Data Display window when selected In several instances for example a test bench that is capable of B
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