Signal Generation Back to Basics
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Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Signal Generation Back to Basics Beyond S-Parameters © Agilent Technologies, Inc. 2007 Page M6- 1 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Agenda The need for creating test signals – Aerospace Defense to Communications From Generating Signals… – No modulation – Analog Modulation – Composite Modulation …To T Simulating Si l ti Si Signals l – Simulating real-life signals Signal Generators Signal Simulation Solutions Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw Agilent From2007 Movies …. Workshop Nov. 1940 - News Flash Disney releases Fantasia with “Fantasound”, a new audio stereophonic sound system Walt Disney orders eight audio oscillators (HP 200B) for the sound production of the movie Fantasia. The 200B was used to calibrate the breakthrough sound system of Walt Disney's celebrated animated film, Fantasia Stimulus/Response Testing Input Output Equalizer Beyond S-Parameters © Agilent Technologies, Inc. 2007 Tone/volume Power Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Aerospace Defense …. TESTING RADAR TRANSMITTERS and RECEIVERs RF Signal Injection ANTENNA IF Signal Injection LNA 1st LO Signal Processor (range and Doppler) 2nd IFA LO Substitution Beyond S-Parameters © Agilent Technologies, Inc. 2007 IF BPF 2nd LO 1st IFA IF BPF Aerospace and Defense Symposium 2007 To Mobile Communications…. EuMw 2007 Agilent Workshop TESTING DIGITAL TRANSMITTERS and RECEIVERs 1011001110001010001 1011001110001010001 RF Signal injection IF Signal Injection Baseband Signal Injection Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Agenda The need for creating test signals – Aerospace Defense to Communications From Generating Signals… – No modulation – Analog Modulation – Composite Modulation …To T Simulating Si l ti Si Signals l – Simulating real-life signals Signal Generators Signal Simulation Solutions Summaryy Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – No Modulation Ti Time Volta age Volta age Continuous Wave (CW) Oscilloscope F Frequency Spectrum Analyzer The sine wave is the basic, non-modulated signal: It is useful for stimulus/response testing of linear components and for Local Oscillator substitution. substitution Available frequencies range from low RF to Millimeter. 6 GHz Beyond S-Parameters © Agilent Technologies, Inc. 2007 Millimeter Microwave RF 20-70 GHz 300 GHz Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Modulation: Where the Information Resides V = V(t) sin[2p fc(t) + f(t)] AM, Pulse FM V = V(t) sin[q(t)] Beyond S-Parameters © Agilent Technologies, Inc. 2007 PM Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals - Analog Modulation Amplitude Modulation Important p Characteristics for Amplitude Modulation Modulation depth %,dB Carrier z Voltage z z Time z z Modulation frequency Where are AM signals used? z z z AM Radio Antenna scan ASK (early digital 100101) Beyond S-Parameters © Agilent Technologies, Inc. 2007 z Modulation frequency (rate) Depth of modulation (Mod Index) Linear AM (%) Log AM (dB) Sensitivity (depth/volt) Distortion % Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Amplitude Modulation Voltage e Carrier Where are AM signals used? Time z z Modulation Beyond S-Parameters © Agilent Technologies, Inc. 2007 z AM Radio A t Antenna scan ASK (early digital 100101) Aerospace and DefenseModulation Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Frequency Modulation Voltag ge IImportant t t Characteristics Ch t i ti for f Frequency Modulation z Time z z z z z Wh Where are FM signals i l used? d? z z z z FM Radio Aviation Flight systems Radar FSK (early digital 1011) Beyond S-Parameters © Agilent Technologies, Inc. 2007 z Frequency Deviation Modulation Frequency dcFM Accuracy Resolution Distortion Sensitivity (dev/volt) Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Frequency Modulation V V= b = DF dev A sin[2pf i [2 fct + bm(t)] (t)] Important Characteristics for Frequency Modulation /Fmod z z Voltage z z Time z z z Beyond S-Parameters © Agilent Technologies, Inc. 2007 Frequency Deviation Modulation Frequency dcFM Accuracy Resolution Distortion Sensitivity (dev/volt) Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Phase Modulation Vo oltage Important Characteristics for Phase Modulation z z Time z z z z Where are Phase Modulated signals used? z z PSK (early digital 1010) Radar(pulse coding) Beyond S-Parameters © Agilent Technologies, Inc. 2007 Phase deviation Modulation Rate Accuracy Resolution Distortion Sensitivity Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Voltage Phase Modulation Where are Phase Modulated signals used? Time z z Beyond S-Parameters © Agilent Technologies, Inc. 2007 PSK (early digital 1010) Radar(pulse coding) Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Pulse Modulation T Rise Rate=1/T time Power On/Off ratio Pulse Width t Important Characteristics for Pulse Modulation z Time z z z Where are Pulse Modulated signals used? z z Radar High g Power Stimulus/Response Communications Beyond S-Parameters © Agilent Technologies, Inc. 2007 1/T 1/t Power z Pulse width Pulse period On/Off ratio Rise time Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Analog Modulation Pulse Modulation T Ri Rise Rate=1/T Where are Pulse Modulated signals used? time Pow wer On/Of f ratio Pulse Width z z t Beyond S-Parameters © Agilent Technologies, Inc. 2007 Time z Radar High Po Power er Stimulus/Response Communications Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Composite Modulation Simultaneous modulation of two Mod Types Independent Amplitude and Phase Modulation Integrated IQ Modulator Q I Independent p FM and Pulse Modulation FM during the pulse = chirp Beyond S-Parameters © Agilent Technologies, Inc. 2007 32 QAM Constellation Diagram Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Composite Modulation Vector Signals (Amplitude and Phase) P l Display Polar Di l Phase 0d deg • Magnitude is an absolute value • Phase is relative to a reference signal (0 degrees) Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Defense Composite Modulation Vector Signal Changes or Modifications Phase 0 deg Magnitude Change Phase 0 deg Phase Change 0 deg 0 deg Both Change Beyond S-Parameters © Agilent Technologies, Inc. 2007 Frequency Change Aerospace and– Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals Composite Modulation Polar Versus I-Q Format Q z Project Signals to “I” and “Q” Axes z Polar to Rectangular Conversion z IQ Pl Plane Sh Shows 2 Thi Things Q-Value Phase 0 deg I I-Value Beyond S-Parameters © Agilent Technologies, Inc. 2007 z z What the modulated carrier is doing relative to the unmodulated d l t d carrier. i What baseband I and Q inputs are required to produce the modulated carrier Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Composite Modulation Transmitting Digital Data -- Bits vs Symbols Binary Data bit = 0,1 Transmission Bandwidth Required Transmitting Digital Bits (f 1 = 0, f 2 = 1 ) f1 f (t) = f2 T 010101010 2/ T Main lobe width is 2 × Sample rate Symbol = Groups/blocks of Bits 2 bits/symbol (00 01 10 11) 3 bit bits/symbol / b l (000 001 …..)) 4 bits/symbol (0000 0001 ..) Symbol Rate = Bit rate # bits per symbol Symbol 1 (00) S b l 2 (01) Symbol f (t) = Symbol 3 (10) Symbol 4 (11) S Beyond S-Parameters © Agilent Technologies, Inc. 2007 2/ S Main lobe width is 2 × Symbol rate Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals – Composite Modulation Digital Modulation Characteristics Modulation format Number of bits per symbol Constellation Transmission bandwidth Q BPSK 1 1 0 I F 01 QPSK Q 2 I 10 11 Q 16 QAM 4 Symbol Rate = #symbols/sec. (Hz) Beyond S-Parameters © Agilent Technologies, Inc. 2007 00 F/2 0000 I F/4 Aerospace and Symposium 2007 Generating Signals – Defense Composite Modulation EuMw 2007 Agilent Workshop Vector Modulation - Important Characteristics Q z z z z Phase IQ Modulation Bandwidth Frequency Response/flatness IQ quadrature skew IQ gain balance 0 deg I flatness Fb w Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and– Defense Symposium 2007 EuMw 2007 Agilent Workshop Generating Signals Composite Modulation Vector Modulation - Where Used Q z I Beyond S-Parameters © Agilent Technologies, Inc. 2007 z Mobile Digital Communications Modern Radars Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Agenda The need for creating test signals – Aerospace Defense to Communications From Generating Signals… – No modulation – Analog Modulation – Composite Modulation …To T Simulating Si l ti Si Signals l – Simulating real-life signals Signal Generators Signal Simulation Solutions Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Simulating Signals Add interference/impairments to user data Multipath signals Multi-path Fading 1011001110001010001 1011001110001010001 Add signal i l impairments i i t Streaming data Recovering User Data g test signal g imperfections Removing Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Simulating SignalsWorkshop Record/playback real signals scenarios RF Signal Injection ANTENNA LNA 1st LO Signal Processor (range and Doppler) 2nd IFA IF BPF 2nd LO Beyond S-Parameters © Agilent Technologies, Inc. 2007 1st IFA IF BPF Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Agenda The need for creating test signals – Aerospace Defense to Communications From Generating Signals… – No modulation – Analog Modulation – Composite Modulation …To T Simulating Si l ti Si Signals l – Simulating real-life signals Signal Generators Signal Simulation Solutions Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Signal Generators • Basic CW Signals • Block Diagram (RF and Microwave) • Specifications • Applications • Analog Signals • Block Diagram (AM, FM, PM, Pulse) • Applications • Vector Signals • Block Diagram (IQ) • Applications Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace Defense Symposium 2007 Basic 2007 CW Signals –and Block Diagram EuMw Agilent Workshop RF Source Synthesizer Section Frac-N Output Section ALC Modulator Output Attenuator Phase Detector VCO divide by X Reference Oscillator Reference Section Beyond S-Parameters © Agilent Technologies, Inc. 2007 ALC Driver ALC Detector ALC = automatic level control Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Block Diagram Reference Section Divide by X Phase Detector Optional External Reference Input Reference Oscillator (TCXO or OCXO) Aging Rate TCXO C O +/- 2ppm/year OCXO +/- 0.1 ppm /year Temp. +/- 1ppm +/- 0.01 ppm Line Voltage +/- 0.5ppm +/- 0.001 ppm Beyond S-Parameters © Agilent Technologies, Inc. 2007 To synthesizer section Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Block Diagram Synthesizer Section Front panel control N = 93.1 Frac-N Error signal 5MHz To output section Phase Detector X VCO 5MHz From reference section Beyond S-Parameters © Agilent Technologies, Inc. 2007 465 5 MHz 465.5 2 Multiplier 931 MHz Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Basic CW Signals – Block Diagram PLL/Fractional-N…suppress phase noise Overall phase noise of signal Reference oscillator Phase detector noise 20logN VCO noise i Beyond S-Parameters © Agilent Technologies, Inc. 2007 Phase-locked-loop (PLL) bandwidth selected for optimum noise performance Broadband noise floor frequency Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Block Diagram Output Section • ALC •maintains level output ALC Modulator power by adding/subtracting From power as needed synthesizer Output Attenuator section Source S output • Output Attenuator •mechanical or electronic •provides p attenuation to achieve wide output range (e.g. -136dBm to +17dBm) ALC Driver ALC Detector Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Block Diagram Microwave Source Reference Section Frac N ALC Modulator Phase Det VCO Sampler Ref Osc YIG Oscillator Phase Detector ALC Driver Frac -N Synthesizer Section Beyond S-Parameters © Agilent Technologies, Inc. 2007 ALC D Detector t t Output Section Output p Attenuator Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Specifications Frequency z z z Range -- Fmin to R t Fmax Resolution – smallest frequency increment Accuracyy – is it where it says y it is Uncertainty Powerr Accuracy = +_ f CW * t aging * t f CW = Frequency q y t aging = t cal = Accuracy = +_152 Hz Beyond S-Parameters © Agilent Technologies, Inc. 2007 cal CW frequency = 1 GHz aging rate = 0.152 ppm/year time since last calibrated = 1 year Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Specifications Amplitude Range ((-136dBm 136dBm to +17dBm) Accuracy (+/- 0.5dB) Resolution (0.02dB) Switching Speed (19ms) Reverse Power Protection Source protected from accidental transmission from DUT What is Pmax out? How accurate is this number? DUT Voltage • • • • • What is Pmin out? Frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Specifications Frequency Sweep Ramp sweep • • • f2 accuracy sweep time resolution f1 t2 t1 time Step sweep • • • accuracy number of points switching time f4 f3 f2 f1 t1 Beyond S-Parameters © Agilent Technologies, Inc. 2007 t2 t3 t4 Aerospace Defense Symposium 2007 Basic 2007 CW Signals –and Specifications EuMw Agilent Workshop Frequency Sweep - Amplitude power level accuracy spec Frequency Sweep • Level Accuracy • Flatness • Source Match (SWR) f1 P2 power sweep range g P1 Beyond S-Parameters © Agilent Technologies, Inc. 2007 frequency f2 po ower Power Sweep • Power Sweep Range • Power Slope Range • Source Match (SWR) flatness spec t1 t2 Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Specifications Spectral Purity • Phase Noise • Spurious CW output Phase noise Non-harmonic spur ~65dBc Harmonic H i spur ~30dBc Sub-harmonics 0 5 f0 0.5 Beyond S-Parameters © Agilent Technologies, Inc. 2007 f0 2f0 Aerospace Defense Symposium 2007 EuMw Agilent Workshop Basic 2007 CW Signals –and Specifications Spectral Purity – Phase Noise CW output Measured as dBc/Hz Frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Basic2007 CW Signals – Applications As a Local Oscillator DUT IF signal transmitter output LO signal Key Specs: • • • • • Frequency Range Accuracy Resolution Output Power Phase Noise Beyond S-Parameters © Agilent Technologies, Inc. 2007 Poor frequency P f accuracy and/or resolution will cause the transmitter output to be at the wrong frequency poor phase noise spreads energy into adjacent channels Aerospace and Defense Symposium 2007 EuMw Agilent Basic2007 CW SignalsWorkshop – Applications In-Channel Receiver Testing The smallest RF signal that will produce a desired baseband output from the receiver Receiver Sensitivity IF signal DUT Key Specs: in-channel signal (cw signal) source • Range (-136dBm ( 136dBm to +17dBm) 17dBm) • Accuracy (+/- 0.5dB) • Resolution (0.02dB) Level (d dBm) p output IF Rejection j Curve -116 116 dB dBm tto – 126 dBm IF Channel Frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw Agilent Basic 2007 CW SignalsWorkshop – Applications Out-of-channel Receiver Testing Receiver Selectivity Spurious Response Immunity IF signal out-of-channel signal (CW and/or modulated signal) DUT source output IF Rejection Curve Key Specs: Frequency Range Output Power Phase Noise Broadband noise Non-harmonic spurious spur from source and/or high levels of phase noise can cause a good receiver to fail Level ((dBm) • • • • • Frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 Basic2007 CW SignalsWorkshop – Applications EuMw Agilent Non-linear Amplifier Testing - TOI f1 DUT output RF f2 K S Key Specs: • • • • • Frequency Range Frequency Accuracy Frequency q y Resolution Output Power Non-harmonic spurious isolato r Two tone Intermodulation Two-tone Distortion test system third order f f2 products will also fall here 1 spurious signals from source can corrupt measurement fL = 2f1 - f2 fU = 2f2 - f1 frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 Basic2007 CW Signals – Applications EuMw Agilent Workshop Out-of-channel Receiver Testing - IMD Intermodulation immunity f1 IF signal isolator f2 Fmod = nF1 + mF2 DUT • • • • • Frequency Range Frequency Accuracy Frequency Resolution Output Power Non-harmonic spurious out-of-channel signals sources output F1 F2 Frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 IF Rejection Curve Intermodulation product Fmod = 2F2 – F1 spur from source Level (d dBm) Key Specs: n= -1,2 , m= 2,-1 Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Basic2007 CW Signals – Applications Stimulus-Response Testing Detector Sweeper Input Detector Fout Fin DUT Fin Fout Key Specs: LO Beyond S-Parameters © Agilent Technologies, Inc. 2007 • • • • • • • Frequency Range Frequency Accuracy Frequency Ramp/step sweep P Power sweep Sweep speed Output Power accuracy Residual FM Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Signal2007 Generators • Basic CW Signals • Block Diagram (RF and Microwave) • Specifications • Applications • Analog Signals • Block Diagram (AM, FM, PM, Pulse) • Applications • Vector Signals • Block Diagram (IQ) • Applications Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent–Workshop Analog Signals Block Diagram Add AM, FM, PM, and Pulse Modulation VCO Output Attenuator ALC Modulator Pulse Mod. Freq. Freq Control Reference Oscillator Beyond S-Parameters © Agilent Technologies, Inc. 2007 ALC Driver FM, PM input AM input Pulse Mod input Aerospace and Defense Symposium 2007 EuMw 2007 Agilent–Workshop Analog Signals Block Diagram Add internal modulation generator VCO Output Attenuator ALC Modulator Pulse Mod. Freq. Control ALC Di Driver AM input FM, PM input Reference Oscillator Beyond S-Parameters © Agilent Technologies, Inc. 2007 FM AM Source Source Pulse Mod input Pulse Source Aerospace Defense Symposium 2007 EuMw 2007 Agilent Workshop Analog Signals –and Applications Receiver Baseband Distortion Receiver In channel signal In-channel (modulated signal) Key Specs: • Frequency Range • Modulation rate/deviation • Modulation Distortion = Receiver Distortion % ( i (dB)/20) x 10-(margin(dB)/20) Example: For a receiver distortion of 5% and a 10 dB test margin, the SG must have < 1.58% mod distortion Distortio n Lev vel (dBm) Required SG M d l ti Modulation distortion Non-linear distortion is characterized by the appearance of harmonics other than the fundamental component in the baseband output Frequency q y Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent–Workshop Analog Signals Applications Pulsed Radar Testing with Chirps RF Si Signall Injection Key Specs: FM during the pulse = chirp • Frequency Range • FM Modulation rate/deviation • Pulse rate, width, rise time LNA 1st LO Signal Processor (range and Doppler) 2nd IFA IF BPF 2nd LO Beyond S-Parameters © Agilent Technologies, Inc. 2007 ANTENNA 1st IFA IF BPF Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Signal2007 Generators • Basic CW Signals • Block Diagram (RF and Microwave) • Specifications • Applications • Analog a og Signals Sg as • Block Diagram (AM, FM, PM, Pulse) • Applications • Vector Signals • Block Diagram (IQ) • Applications Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Block Diagram IQ Modulation 01 I : Q 00 Carrier I p/ 2 Q : 11 z z z Beyond S-Parameters © Agilent Technologies, Inc. 2007 Good Interface with Digital Signals and Circuits Can be Implemented with Simple Circuits F t accurate Fast, t state t t change h 10 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Vector Signals – Workshop Block Diagram Adding the IQ modulator Synthesizer VCO I-Q Modulator Output p/2 Freq. C t l Control ALC Driver Q Reference Beyond S-Parameters © Agilent Technologies, Inc. 2007 I Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Block Diagram Baseband IQ signal generation Analog Reconstruction Filters Symbol y Mapping and Baseband Filters Pattern RAM 00 -> 1 1+j1 j1 11000101101 01001011100 10101010 01 -> -1+j1 10 -> -1-j1 11 -> 1-j1 Beyond S-Parameters © Agilent Technologies, Inc. 2007 DAC I DAC Q Aerospace and Defense Symposium 2007 EuMw 2007 Agilent–Workshop Vector Signals Block Diagram Baseband Generator: Baseband Filters Fast Transitions Require Wide Bandwidths Frequency Frequency Filtering Slows Down Transitions and Narrows the Bandwidth Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Vector2007 Signals – Block Diagram Adding an internal Baseband Generator Synthesizer VCO I-Q Modulator Output p/2 Freq. C t l Control ALC Driver Q DAC I Reference DAC Pattern RAM and Symbol Mapping Baseband Generator Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Applications • • • • Formatt Specific F S ifi Signal Si lG Generation ti Receiver Sensitivity Receiver Selectivity Component Distortion Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent–Workshop Vector Signals Applications Digital Format Access Schemes Different time - different Users One User FDMA Differ channel - different Users CDMA Same channel – many users Beyond S-Parameters © Agilent Technologies, Inc. 2007 TDMA OFDM Different time - different Users Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Applications Format Specific Modulation GSM: slots multiple users, same frequency, different time Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Applications Digital Receiver Sensitivity The smallest modulated RF signal that will produce a specified BER from the receiver DUT RF DAC Baseband DSP Amp plitude RF LO Payload Data BER Spec Line frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 BER Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Applications Digital Receiver Sensitivity T ti Testing a -110 110 dB sensitivity iti it digital di it l receiver: i X= Failed unit O=Passed unit -110 dB specification X X X -110 dB specification Set source to -111 dBm X X X X Actual output power= -114 dBm O Set source to -115 115 dBm Frequency Case 1: Source has +/-5 dB of output power accuracy at -100 to -120 dBm output power. Beyond S-Parameters © Agilent Technologies, Inc. 2007 O O O Actual output power= -112 dBm O Frequency Case 2: Source has +/-1 dB of output power accuracy at -100 to -120 dBm output power. Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Vector2007 Signals – Applications Receiver Sensitivity – Connected Solutions • Simulated portion RF IF I Demodulator Q A/D Converter Baseband De-Coding DUT RF/IF BER Signal Generator Beyond S-Parameters © Agilent Technologies, Inc. 2007 Simulation Software Signal y Analyzer Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Vector2007 Signals – Applications Receiver Selectivity (Blocking Tests) In-channel signal g (modulated signal) RF DAC Out-of-channel O t f h l signal i l (CW or modulated signal) Baseband DSP RF LO Lev vel (dBm) IF Rejection Curve Spur from source and/or high levels of phase noise can cause a good receiver to fail Sensitivity specification F Frequency Beyond S-Parameters © Agilent Technologies, Inc. 2007 Payload Data Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Vector Signals – Workshop Applications Component Distortion – Adjacent Channel Power Ratio DUT Spectral p Output p from amplifier p ACPR Input from VSG Spectral regrowth ACP Margin Margin (dB) 0 Error contribution (dB) 3.0 Beyond S-Parameters © Agilent Technologies, Inc. 2007 1 2 3 4 5 10 15 2.5 2.1 1.8 1.5 1.2 0.4 0.2 Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Vector2007 Signals – Applications Component Distortion – Error Vector Magnitude OFDM Si Signall 400 MHz Bandwidth DAC Q Q Magnitude Error Q (IQ error mag) I Error Vector Magnitude Test Signal f Ideal (Reference) Signal Phase Error (IQ error phase) I Beyond S-Parameters © Agilent Technologies, Inc. 2007 I Aerospace and Defense Symposium 2007 EuMw 2007 Agilent– Workshop Vector Signals Applications Component Distortion – EVM Beyond S-Parameters © Agilent Technologies, Inc. 2007 Measured EVM = -30 dB, 3.3% Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop Agenda The need for creating test signals – Aerospace Defense to Communications From Generating Signals… – No modulation – Analog Modulation – Composite Modulation …To T Simulating Si l ti Si Signals l – Simulating real-life signals Signal Generators Signal Simulation Solutions Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Simulating real signal environments Fading Baseband SW Waveform Capture and Playback Baseband SW Signal Creation Create Impairments Import/export Custom Digital Data Digital Signal Interface Stream Data I t Internal l BBG Vector Baseband IQ generation Signal External BBG Generato r Si Signal l Create Standard Creation Signals SW User H d Hardware RF/Microwave Signals Remove test signal imperfections pe ect o s Vector Signal Analyzer Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Signal2007 Simulation Solutions Remove Test Signal Imperfections BBG Add Predistortion (corrections) Signal Software LAN/GPIB VSG Measurement Results Measure Modulated Signal VSA Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Remove Test Signal Imperfections – IQ Flatness Source of error – I/Q modulator, RF chain, IQ path Result – passband tilt, tilt ripple, ripple and roll off Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw Agilent Workshop Signal2007 Simulation Solutions Remove Test Signal imperfections – IQ flatness Solution – measure vector signal generator and apply predistortion Tradeoff – calculation time, valid cal time Typical application – wideband, multitone, and multicarrier 500 MHz UWB 32 tones - 80 MHz 2.4 dB Before 0.1 dB < 3 dB After Beyond S-Parameters © Agilent Technologies, Inc. 2007 6-8 dB Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Removing Test Signal Imperfections - IMD Before Predistortion Measured in-band IMD = -40 dBc Beyond S-Parameters © Agilent Technologies, Inc. 2007 After Predistortion Measured in-band IMD = -84 dBc Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Removing Test Signal Imperfections – Group Delay Before Predistortion EVM -30 dB, 3.3% Beyond S-Parameters © Agilent Technologies, Inc. 2007 After Predistortion EVM –34 dB, 2% Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Non-linear Amplifier Testing DUT output RF Intermodulation Di t ti Distortion • Improved IMD suppression (typically > 80 dBc) • Correct generator with additional devices in the loop • Lower overall cost-of-test for large # tones Signal Studio – Enhanced Multitone • Same hardware for ACPR/NPR distortion tests Up to 1024 tones Set relative tone power Set relative tone phase 80 MHz correction BW plot CCDF p Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Adding Impairments to Signals – Fading Faded signal R Receiver i transmission channel Interferers SW and interface hw Beyond S-Parameters © Agilent Technologies, Inc. 2007 Faded analog RF, IF, or IQ for receiver test Faded digital IQ baseband for digital subsystem test BER/PER analysis Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop RF Capture & Playback RF Signal Injection ANTENNA LNA 1st LO Record signals off the air Transfer files to a PC equipped with Baseband Studio and re-format Stream St them th iinto t th the V Vector t PSG signal i l generator t for f playback l b k Signal Processor (range and Doppler) 2nd IFA IF BPF 2nd LO Beyond S-Parameters © Agilent Technologies, Inc. 2007 1st IFA IF BPF Aerospace and Defense Symposium 2007 Signal2007 Simulation Solutions EuMw Agilent Workshop Digital Capture & Playback Capture p data from the digital g section of a transmitter Digital bus Capture digital I/Q signals DUT Test stimulus to the digital section of a receiver Digital bus Playback digital I/Q signals DUT Beyond S-Parameters © Agilent Technologies, Inc. 2007 Aerospace and Defense Symposium 2007 EuMw 2007 Agilent Workshop THANK YOU! Beyond S-Parameters © Agilent Technologies, Inc. 2007
