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Network Analyzer BasicsNetwork Analyzer BasicsNetwork Analysis is NOT. RouterBridgeRepeaterHubYour IEEE 802.3 X.25 ISDNswitched-packet data streamis running at 147 MBPS with-9a BER of 1.523 X 10 . . .Network Analyzer BasicsNetwork Analyzer BasicsLowDielectricsR, L, C'sPassiveComplexRFICsMMICsT/R plersMultipliersDiodesDevice typeVCOsVTFsOscillatorsModulatorsVCAtten’sRFIC testHarm. Dist.LO stabilityImage Rej.VNATG/SASNANF Mtr.Param. An.Power Mtr.TransistorsDet/ScopeFull callsequencePulsed S-parm.Pulse /FlatnessDC CW Swept lat. Compr'nPhase/GD AM-PMIsolationRtn Ls/VSWRImpedanceS-parametersImped. An.Network Analyzer BasicsNoise2-toneMulti-ComplextonePulsed-Stimulus typeProtocolComplexNetwork Analyzer BasicsLightwave Analogy to RF EnergyIncidentReflected84000Ded. ltersCouplersBridgesSplitters, aptersOpens, shorts, loadsDelay linesCablesTransmission linesWaveguideResonatorsDevice Test Measurement ModelSimpleHighWhat Types of Devices are Tested?Why Do We Need to Test Components? Verify specifications of “building blocks” for morecomplex RF systems Ensure distortionless transmissionof communications signalsTransmitted– linear: constant amplitude, linear phase / constant groupdelay– nonlinear: harmonics, intermodulation, compression, AMto-PM conversionLightwave Ensure good match when absorbingpower (e.g., an antenna)DUTRFKPWRNetwork Analyzer BasicsNetwork Analyzer Basics1FM 97

Network Analyzer BasicsThe Need for Both Magnitude and PhaseAgendaS211. Completecharacterization oflinear networks S11S22S122. Complex impedanceneeded to designmatching circuits4. Time-domaincharacterization Mag3. Complex valuesneeded for devicemodelingHigh-frequency transistor modelTime 5. Vector-error correctionErrorBase CollectorMeasured What measurements do we make? Transmission-line basics Reflection and transmissionparameters S-parameter definitionNetwork analyzer hardware Signal separation devices Detection types Dynamic range T/R versus S-parameter test setsError models and calibration Types of measurement error One- and two-port models Error-correction choices Basic uncertainty calculationsExample measurementsAppendixActualEmitterNetwork Analyzer BasicsNetwork Analyzer BasicsTransmission line ZoTransmission Line Basics-I Zo determines relationship between voltage and currentwavesZo is a function of physical dimensions and εrZo is usually a real impedance (e.g. 50 or 75 ohms)1.5Twisted-pair1.3a1.2bHigh frequencies wavelength or length of transmissionmedium need transmission lines for efficient powertransmission matching to characteristic impedance (Z o) isvery important for low reflection and maximumNetwork Analyzer Basicspower transfer measured envelope voltage dependent onεrCoaxialw2Coplanar50 ohm standard1.00.90.8power handling capacitypeaks at 30 ohms0.6w0.5102030405060 70 80 90 100characteristic impedancefor coaxial airlines (ohms)MicrostripNetwork Analyzer BasicsTransmission Line Terminated with ZoZs ZoLoad Power(normalized)1.10.7w1RSFor complex impedances, maximumpower transfer occurs when ZL ZS*(conjugate match)Rs1.2hhPower Transfer EfficiencyRLattenuation islowest at 77 ohms1.4Waveguidenormalized values Low frequencies wavelengths wire length current (I) travels down wires easily for efficientpower transmission measured voltage and current not dependent onposition along wireZo characteristicimpedanceoftransmission lineZo jX1-jX0.8Vinc0.6RL0.40.2Vrefl 0! (all the incident poweris absorbed in the load)0012345678910RL / RSFor reflection, a transmission lineterminated in Zo behaves like an infinitelylong transmission lineMaximum power is transferred when RL RSNetwork Analyzer BasicsNetwork Analyzer Basics2

Network Analyzer BasicsTransmission Line Terminated with 25 ΩTransmission Line Terminated withShort, OpenZs ZoZs ZoZL 25 ΩVincVincVreflNetwork Analyzer BasicsVreflIn-phase (0o) for open,out-of-phase (180o) for shortFor reflection, a transmission lineterminated in a short or open reflectsall power back to sourceNetwork Analyzer BasicsHigh-Frequency Device CharacterizationReflection RVreflectedΓ VincidentReturn loss -20 log(ρ),BReflectedStanding wave patterndoes not go to zero aswith short or openAReflectedIncident ATransmittedRIncidentSWRS-ParametersS11, S22ReflectionCoefficientΓ, ρReturnLossImpedance,AdmittanceR jX,G jBρΦ ZL ZOZ L ZOΓ Voltage Standing WaveRatioEmaxVSWR Emin 1 ρ1-ρB RGroupDelayTransmissionCoefficientΤ,τFull reflection(ZL open, short)No reflection(ZL Zo)Gain / LossS-ParametersS21, S12ρEmaxEminTRANSMISSIONREFLECTION ρ1 dBRL0 dB1VSWR 0InsertionPhaseNetwork Analyzer BasicsNetwork Analyzer BasicsSmith Chart ReviewTransmission Parameters. jXPolar plane90oV IncidentDUT1.0.8V Transmitted.60 R.4 180 o-o.20Transmission Coefficient 0-jXRectilinear impedanceplane-90VConstant XΓ Γ 1V0 180ZL Γ 1O(open)0TransInsertion Loss (dB) - 20 LogConstant RZ L 0 (short) V Incident oZ L ZoSmith Chart mapsrectilinearimpedanceplane onto polarplaneV TransmittedΤVOGain (dB) 20 LogVSmith chartNetwork Analyzer BasicsNetwork Analyzer Basics3TransInc - 20 logInc 20 logτττ φ

Network Analyzer BasicsCriteria for Distortionless TransmissionLinear NetworksLinear Versus Nonlinear BehaviorA * Sin 360o * f (t - to)ALinear behavior: TimetoA phase shift to * 360o * fDUTInputFrequencyMagnitudef1TimeLinear phase overbandwidth ofinterestConstant amplitude overbandwidth of interestOutputFrequencyPhaseSin 360o * f * tinput and output frequencies arethe same (no additionalfrequencies created)output frequency only undergoesmagnitude and phase changeNonlinear behavior:f1 FrequencyTime fFrequency1output frequency mayundergo frequency shift(e.g. with mixers)additional frequenciescreated (harmonics,intermodulation)FrequencyNetwork Analyzer BasicsNetwork Analyzer BasicsPhase Variation with FrequencyMagnitude Variation with FrequencyF(t) sin wt 1 /3 sin 3wt 1 /5 sin 5wtF(t) sin wt 1/3 sin 3wt 1/5 sin 5wtLinear FrequencyFrequency0 FrequencyFrequency-360 Network Analyzer BasicsDeviation from Linear PhaseGroup DelayUse electrical delay toremove linear portion ofphase responseLinear electrical lengthaddedRF filter responseFrequencyωAverage delay φPhase 1 /DivoyieldsFrequencyGroup delay rippletoφPhaseDeviation from linearphaseoPhase 45 /Div tg ω(Electrical delay function)Low resolutionFrequency-180 FrequencyNetwork Analyzer BasicsFrequencyTimeFrequencyGroup Delay (tg) d φdωFrequencyφωφHigh resolution 1360 o*dφdf in radians/sec in degreesf in Hertz (ω 2 π f)Network Analyzer BasicsNetwork Analyzer Basics4 in radiansgroup-delay ripple indicates phase distortionaverage delay indicates electrical length of DUTaperture of measurement is very important

Network Analyzer BasicsCharacterizing Unknown DevicesUsing parameters (H, Y, Z, S) to characterizedevices:PhasePhaseWhy Measure Group Delay? ff d φdω GroupDelayGroupDelay d φdωgives linear behavioral model of our devicemeasure parameters (e.g. voltage and current) versusfrequency undervarious source and load conditions(e.g. short and open circuits)compute device parameters from measured datapredictcircuit performanceunder any sourceand V1 h11I1 h12V2I1 y11V1 y12V2V1 z11I1 z12I2I2 h21I1 h22V2I2 y21V1 y22V2V2 z21I1 z22I2ffSame p-p phase ripple can result in differentgroup delayNetwork Analyzer Basics V2 0(requires short circuit)h12 V1V2I1 0(requires open circuit)Network Analyzer BasicsMeasuring S-ParametersWhy Use S-Parameters? h11 V1I1Reflectedb1b1TransmittedS 21 Incidenta2 0b1 1Z0S 11ForwardS 11 SIncidenta1relatively easy to obtain at high frequencies measure voltage traveling waves with a vector network analyzer don't need shorts/opens which can cause active devices to oscillateor self-destructrelate to familiar measurements (gain, loss, reflection coefficient .)can cascade S-parameters of multiple devices to predict systemperformancecan compute H, Y, or Z parameters from S-parameters if desiredS 21IncidentTransmittedcan easily importanduse S-parameterfiles in our electronica1b2simulation tools S11a2 0S 22 2 a1a2 0S 12 ReflectedIncidentTransmittedIncidentb2 a2ba1 01 a2a1 0DUTS22Port 2 ReflectedPort 1a2IncidentSTransmitted12a1 0Z0DUTLoadb1 S11a1 S12 a 2b1b 2 S21 a1 S22 a 2Network Analyzer BasicsTransmittedS 12S 22b2ReverseReflecteda2IncidentNetwork Analyzer BasicsEquating S-Parameters with CommonMeasurement TermsCriteria for Distortionless TransmissionNonlinear Networks S11 forward reflection coefficient (input match)S22 reverse reflection coefficient (output match)S21 forward transmission coefficient (gain or loss)S12 reverse transmission coefficient (isolation) Remember, S-parameters areinherently complex, linearquantities -- however, we oftenexpress them in a log-magnitudeformatSaturation, crossover,intermodulation, and other nonlineareffects can cause signal distortionEffect on system depends on amountand type of distortion and systemarchitectureTimeFrequencyNetwork Analyzer BasicsNetwork Analyzer Basics5TimeFrequency

Network Analyzer BasicsWhat is the Difference BetweenNetwork and Spectrum Analyzers?Measuring Nonlinear Behavior8563ALPFSPECTRUM ANALYZER.RL 0 dBmATTEN10 dB10 dB / DIVMeasuresknownsignalAmplitude8563AAmplitude RatioMost common measurements: using a network analyzer andpower sweeps gain compression AM to PM conversion using a spectrum analyzer source(s) harmonics, particularly secondand third intermodulation products resultingfrom two or more RFcarriersSPECTRUM ANALYZERGHz9 k Hz -2 6.5MeasuresunknownsignalsFrequencyFrequency9 k Hz -2 6.5 GHzNetwork analyzers: DUT CENTER 20.00000 MHzRB 30 HzVB 30 HzLPFSPAN 10.00 kHzST 20 sec Network Analyzer BasicsSpectrum analyzers:measure components, devices,circuits, sub-assembliescontain source and receiverdisplay ratioed amplitude and phase(frequency or power sweeps)offer advanced error correction measure signal amplitude characteristicscarrier level, sidebands, harmonics.)can demodulate (& measure) complexsignalsare receivers only (single channel)can be used for scalar component test (nophase) with tracking gen. or ext. source(s)Network Analyzer BasicsAgendaGeneralized Network AnalyzerBlock Diagram IncidentWhat measurements do we make?Network analyzer hardwareError models and calibrationExample B)RECEIVER / DETECTORPROCESSOR / DISPLAYNetwork Analyzer BasicsNetwork Analyzer BasicsIncidentSourceSignal ATION INCIDENT ( R)Supplies stimulus for systemSwept frequency or powerTraditionally NAs used separatesourceMost Agilent analyzers soldtoday have integrated,synthesized sourcesREFL ECT ED(A)TRANSMITT ED(B)RECEIVER / DETECTORPROCESSOR / DISPLAY measure incident signal for referenceseparate incident and reflected signalssplitterbridgedirectionalcouplerNetwork Analyzer BasicsNetwork Analyzer Basics6DetectorTest Port

Network Analyzer BasicsInteraction of Directivity with theDUT (Without Error Correction)DirectivityDirectivity is a measure of how well acoupler can separate signals movingin opposite directionsData MaxDevice(desired reflectedsignal)DirectivityDUT RL 40 dBReturn Loss(undesired leakagesignal)030Add in-phase60DeviceFrequencyDirectivityDirectional CouplerNetwork Analyzer BasicsDeviceTest portData MinData Vector SumDirectivityAdd out-of-phase(cancellation)Network Analyzer BasicsIncidentDetector TypesTransmittedBroadband Diode DetectionDUTReflectedSOURCEScalar broadband(no phaseinformation)DiodeSIGNALSEPARATIONINCIDENT ( R)REFL ECT ED(A)TRANSMITT ED(B)RECEIVER / DETECTORPROCESSOR / DISPLAYDCEasy to make broadbandInexpensive compared to tuned receiver Good for measuring frequency-translating devices Improve dynamic range by increasing power Medium sensitivity / dynamic range RFAC Tuned ReceiverIF F LO F RFRFADC / DSPVector(magnitude andphase)IF FilterLO10 MHzNetwork Analyzer Basics26.5 GHzNetwork Analyzer BasicsNarrowband Detection - Tuned ReceiverComparison of Receiver TechniquesBroadband(diode)detectionADC / DSP0 dBBest sensitivity / dynamic range Provides harmonic / spurious signalrejection Improve dynamic range by increasingpower, decreasing IF bandwidth, oraveraging Trade off noise floor andmeasurement speed0 dBNarrowband(tuned-receiver)detection 10 MHz-50 dB-50 dB-100 dB-100 dB-60 dBm Sensitivityhigher noise floor false responses -100 dBm Sensitivity high dynamic rangeharmonic immunityDynamic range maximum receiver power receiver noise floor26.5 GHzNetwork Analyzer BasicsNetwork Analyzer Basics7

Network Analyzer BasicsT/R Versus S-Parameter Test SetsDynamic Range and AccuracySourceSource-10Transfer switch Error (dB, deg)S-Parameter Test SetTransmission/Reflection Test SetError Due to Interfering Signal100Dynamic rangeis very importantfor measurementaccuracy!phase error1magn error0.1RRBAPort 1Port RF always comes out port1 port 2 is always receiver response, one-port calNetwork Analyzer Basicsavailable-70Interfering signal (dB)Network Analyzer BasicsProcessor / DisplayIncidentPort 2Port 1DUT 0.001BA DUTRevRF comes out port 1 or port2forward and reversemeasurementstwo-port calibrationpossibleInternal Measurement AutomationTransmittedDUTSimple: recall statesMore powerful:50 MH-20GHzNETWORK ANYZERACTIVECHANNELC H 2 S TA R T 775. 000 000 MH zC H 1 S TA R T 775. 000 000 MH zReflectedENTRYS TO P 925. 000 000 MH zS TO P 925. 000 000 MH zH ldSOURCERESPONSEPA S S2C orP RmSIGNALSEPARATION880.435 000 M H z1PA S S1REFL ECT ED(A)STIMULUSH ldTRANSMITT ED(B)P Rm R CHANNELINSTRUMENTSTATED uplex er T est - Tx -A nt and Ant - RxTR LS 839.470 000 M H zCH2CH1S 12S 21log MA Glog MA G10 dB/10 dB/Test sequencing1C orINCIDENT(R)R E F 0 dBR E F 0 dBHP-IB STATUS1 - 1.2468 dB1 - 1.9248 dBPORT 1PORT 2RECEIVER / DETECTOR PROCESSOR / DISPLAYCH2 START 775.000 000 MHzCH1 START 775.000 000 MHz STOP 925.000 000 MHzSTOP 925.000 000 MHzHld PASS2IBASIC Cor markerslimit linespass/fail indicatorslinear/log formatsgrid/polar/SmithchartsPRm 880.435 000 MHz1available on 8753/ 8720familieskeystroke recordingsome advanced functionsABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 - / * ( ) & "" " , . / ? ; : ' [ ]1 ASSIGN @Hp8714 TO 8002 OUTPUT @Hp8714;"SYST:PRES; *WAI"3 OUTPUT @Hp8714;"ABOR;:INIT1:CONT OFF;*WAI"available on 8712 familysophisticated programscustom user interfaces4 OUTPUT @Hp8714;"DISP:ANN:FREQ1:MODE SSTOP"5 OUTPUT @Hp8714;"DISP:ANN:FREQ1:MODE CSPAN"6 OUTPUT @Hp8714;"SENS1:FREQ:CENT 175000000 HZ;*WAI"7 OUTPUT @Hp8714;"ABOR;:INIT1:CONT OFF;:INIT1;*WAI"8 OUTPUT @Hp8714;"DISP:WIND1:TRAC:Y:AUTO ONCE"9 OUTPUT @Hp8714;"CALC1:MARK1 ON"PASSHld10 OUTPUT @Hp8714;"CALC1:MARK:FUNC BWID"11 OUTPUT @Hp8714;"SENS2:STAT ON; *WAI"112 OUTPUT @Hp8714;"SENS2:FUNC 'XFR:POW:RAT 1,0';DET NBAN; *WAI"1CorPRm13 OUTPUT @Hp8714;"ABOR;:INIT1:CONT OFF;:INIT1;*WAI"Duplexer Test - Tx-Ant and Ant-Rx839.470 000 MHzCH2CH1S12S21log MAGlog MAG10 dB/10 dB/REF 0 dBREF 0 dB14 OUTPUT @Hp8714;"DISP:WIND2:TRAC:Y:AUTO ONCE"1 -1.2468 dB1 -1.9248 dB15 OUTPUT @Hp8714;"ABOR;:INIT1:CONT ON;*WAI"16 ENDNetwork Analyzer BasicsNetwork Analyzer BasicsAgilent’s Series of HF Vector AnalyzersAgilent’s LF/RF Vector AnalyzersMicrowave Combination NA / SA8510C series8720ET/ES series 13.5, 20, 40 GHzeconomicalfast, small, integratedtest mixers, high-poweramps 110 GHz in coaxhighest accuracymodular, flexiblepulse systemsTx/Rx moduletest4395A/4396B RF8712ET/ES series 1.3, 3 GHzlow costnarrowband andbroadbanddetectionIBASIC / LANE5100A/B8753ET/ES series 500 MHz (4395A), 1.8 GHz (4396B)impedance-measuring optionfast, FFT-based spectrum analysistime-gated spectrum-analyzer optionIBASICstandard test fixtures3, 6 GHzhighest RFaccuracyflexible hardwaremore featuresOffset and harmonicRF sweeps LF Network Analyzer BasicsNetwork Analyzer Basics8180, 300 MHzeconomicalfast, smalltarget markets: crystals, resonators, filtersequivalent-circuit modelsevaporation-monitor-function option

Network Analyzer BasicsAgendaSpectrum Analyzer / Tracking GeneratorRF in IF8563ASPECTRUM ANALYZER9 k Hz -2 6.5 GHzLO DUT Spectrum analyzer TG out f IFDUTTracking generatorWhy do we even need error-correction andcalibration? It is impossible to make perfect hardware It would be extremely expensive to make hardwaregood enough to eliminate the need for errorcorrectionKey differences from network analyzer: What measurements do wemake?Network analyzer hardwareError models and calibrationExample measurementsAppendixone channel -- no ratioed or phase measurementsMore expensive than scalar NA (but better dynamic range)Only error correction available is normalization (and possiblyopen-short averaging)Poorer accuracySmall incremental cost if SA is required for other measurementsNetwork Analyzer BasicsNetwork Analyzer BasicsMeasurement Error ModelingCalibration TopicsWhat measurements do wemake? Network analyzer hardware Error models and calibration measurement errors what is vector errorcorrection? calibration types accuracy examples calibration considerations Example measurements Appendix CAL-CREALSystematic errors due to imperfections in the analyzer and test setup assumed to be time invariant (predictable)Random errors vary with time in random fashion (unpredictable) main contributors: instrument noise, switch and connectorrepeatabilityDrift errors due to system performance changing after a calibration hasbeen done primarily caused by temperature eRANDOMDRIFTNetwork Analyzer BasicsNetwork Analyzer BasicsSystematic Measurement ErrorsTypes of Error Correction RACrosstalkDirectivityresponse (normalization)simple to performonly corrects for tracking errorsthrustores reference trace in memory,then does data divided by memoryvectorrequires more standardsrequires an analyzer that can measure phaseaccounts for all major sources of systematic error B DUT Frequency response reflection tracking (A/R) transmission tracking (B/R)SourceMismatchLoadMismatchSHORTS11aSix forward and six reverse errorterms yields 12 error terms for twoport devicesNetwork Analyzer BasicsNetwork Analyzer Basics9thruOPENS11mLOAD

Network Analyzer BasicsWhat is Vector-Error Correction? Reflection: One-Port ModelError AdapterIdealRF inProcess of characterizing systematic error termsmeasure known standardsremove effects from subsequent measurements1-port calibration (reflection measurements)only 3 systematic error terms measureddirectivity, source match, and reflection trackingFull 2-port calibration (reflection and transmission measurements)12 systematic error terms measuredusually requires 12 measurements on four known standards(SOLT)Standards defined in cal kit definition filenetwork analyzer contains standard cal kit definitionsCAL KIT DEFINITION MUST MATCH ACTUAL CAL KIT USED!User-built standards must be characterized and entered into usercal-kitRF in1ED Directivity S11AED S11A ActualTo solve for error terms,S11Awe measure 3 standardsS11M ED to generate 3 equations1ES S11AERTand 3 unknownsAssumes good termination at port two if testing two-port devicesIf using port 2 of NA and DUT reverse isolation is low (e.g., filter passband):assumption of good termination is not validtwo-port error correction yields better results S11M MeasuredERT ES Source MatchS11MS11M Network Analyzer BasicsNetwork Analyzer BasicsTwo-Port Error CorrectionBefore and After One-Port CalibrationReverse modelForward model0Port 1Port 1EXPort 2S21a1data before 1-portcalibrationa120S 21AESEDE RTVSWREL' rev load matchETT' rev transmission trackingEX' rev isolation1.001600012000MHz Network Analyzer BasicsAS22b2E S'AED'a2S12 AE TT'EX'E D' rev directivityE S' rev source matchE RT' rev reflection tracking S11AEL fwd load matchETT fwd transmission trackingEX fwd isolation b1Aa2ED fwd directivityE S fwd source matchERT fwd reflection trackingdata after 1-portcalibration60ELE L'S 121.11.01b2ETTS22 AS11Ab140Port 2E RT'2.0Return Loss (dB)ERT Reflection trackingS11AESEach actual S-parameter is a functionof all four measured S-parametersAnalyzer must make forward andreverse sweep to update any one SparameterLuckily, you don't need to know theseequations to use network analyzers!!!S 22a E RTE RT 'E TTETT '(1 11mE S )(1 22 mE S ' ) E L ' E L ( 21m)()SS ED'S E X S12 m E X ' EDE RT 'E RTETTE TT '( 22m)( 1 11mE S ) E L ' ( 21m)( 12m)DDXS E 'S ES ES EX 'S12a E RTE RT 'E TTE TT '(1 11mE S )(1 22 mE S ' ) E L ' E L ( 21m)()S EDS ED'S E X S12 m E X 'E TT 'E RTSL( 12m)(1 11m( E E ' ))S EX 'S EDS21a E RTE RT 'E TTE TT '(1 11mE S )(1 22 mE S ' ) E L ' E L ( 21m)() ED ED' E X S12 m E X 'SSSE TTE RT '()(1 ( E S ' E L ))S21m E XS22 m E D 'S11a E RTE RT 'E TTETT '(1 11mE S )(1 22 mE S ' ) E L ' E L ( 21m)()S E D'S ED 'S E X S12 m E X 'E RTE RT 'E TTE TT 'S ') EL(( 11m)(1 E)()S EDS 22 m E D 'S 21m E X S12 m E X 'Network Analyzer BasicsCrosstalk: Signal Leakage BetweenTest Ports During TransmissionErrors and Calibration StandardsDUTUNCORRECTEDFULL 2-PORTCan be a problem with:high-isolation devices (e.g., switch in open position)high-dynamic range devices (some filter stopbands) Isolation calibrationadds noise to error model (measuring near noise floor of system)only perform if really needed (use averaging if necessary)if crosstalk is independent of DUT match, use two terminationsif dependent on DUT match, use DUT with termination on outputRESPONSE DUT OPENthru ConvenientGenerally notaccurateNo errors removed LOAD Easy to performUse when highestaccuracy is notrequiredRemovesfrequencyresponse errorENHANCED-RESPONSE DUTLOADNetwork Analyzer BasicsCombines response and 1-portCorrects source match for transmissionmeasurementsNetwork Analyzer Basics10SHORTOPENOPENLOADLOADDUT DUTSHORTDUT LOAD1-PORTSHORTFor reflectionmeasurementsNeed good termination forhigh accuracy with twoport devicesRemoves these errors:DirectivitySource matchReflection trackingthruDUT Highest accuracyRemoves theseerrors:DirectivitySource, loadmatchReflection trackingTransmissiontrackingCrosstalk

Network Analyzer BasicsCalibration SummaryReflectionTest Set (cal type)T/RReflection tracking Directivity Source match Load matchSHORTRemember: convert all dB values tolinear for uncertainty calculations!S-parameter(one-port) Reflection Example Using a One-Port Cal(two-port)OPENDirectivity:40 dB (.010)T/RDUTS-parameter(two-port)(response, isolation).158error can be corrected Transmission Tracking Crosstalk Source match ( Load matcherror cannot be correctedenhanced response cal correctsfor source match duringtransmission measurements*-20 * log (.158 - .100 - .010) 26.4 dB ( 10.4 dB)Network Analyzer BasicsUsing a One-Port Cal AttenuatorLoadmatch:18 dB(.126)10 dB attenuator(.316) SWR 1.05 (.024)Transmission Example Using ResponseCalMeasurementuncertainty:-20 * log (.158 .039) 14.1 dB (-1.9 dB)-20 * log (.158 - .039) 18.5 dB ( 2.5 dB)RL 18 dB (.126)RL 14 dB (.200)Thru calibration (normalization) builds error intomeasurement due to source and load match interactionDUT16 dB RL (.158)1 dB loss (.891).158CalibrationUncertainty (1 ρS ρL)Low-loss bi-directional devicesgenerally require two-portcalibrationWorst-case error .010 .010 .019 .039 for low measurement uncertainty(.891)(.316)(.126)(.316)(.891) .010(.891)(.024)(.891) .019 (1 (.200)(.126) 0.22 dBNetwork Analyzer BasicsNetwork Analyzer BasicsFilter Measurement with Response CalSource match 14 dB (.200)Measurement uncertainty:-20 * log (.158 .100 .010) 11.4 dB (-4.6dB)(.891)(.126)(.891) .100* )Network Analyzer BasicsDirectivity:40 dB (.010)2016 dB RL (.158)1 dB loss (.891)Test Set (cal type)Transmissionρ or loss(linear) 10 -dB( )Loadmatch:18 dB(.126)LOADDUT1 dB loss (.891)16 dB RL (.158)Measuring Amplifiers with a Response CalLoad match 18 dB(.126)1Source match 14 dB (.200)DUT16 dB RL(.158)Load match 18 dB(.126)1(.126)(.158) .020(.126)(.158) .020(.126)(.891)(.200)(.891) .020(.158)(.200) .032(.158)(.200) .032Total measurementuncertainty: 0.60 0.22 0.82 dB-0.65 - 0.22 - 0.87 dBTotal measurementuncertainty: 0.44 0.22 0.66 dB-0.46 - 0.22 - 0.68 dBMeasurement uncertainty 1 (.020 .020 .032) 1 .072 0.60 dB- 0.65 dBNetwork Analyzer BasicsNetwork Analyzer Basics11Measurement uncertainty 1 (.020 .032) 1 .052 0.44 dB- 0.46 dB

Network Analyzer BasicsFilter Measurementsusing the EnhancedResponse CalibrationEffective source match 35 dB!DUT1 dB loss (.891)16 dB RL (.158)Sourcematch 35dB (.0178)Load match 18 dB(.126)Using the Enhanced ResponseCalibration Plus an AttenuatorCalibration Uncertainty (1 ρS ρL)10 dB attenuator (.316)SWR 1.05 (.024 linear or 32.4dB)Analyzerload match 18 dB (.126)Calibration Uncertainty (1 ρS ρL) (1 (.0178)(.126) .02 dBDUT1 dB loss (.891)16 dB RL (.158)Source match 35 dB(.0178)1Measurement uncertainty 1 (.020 .0018 .0028)(.126)(.158) .020 1 .0246 0.211 dB(.126)(.891)(.0178)(.891) .0018- 0.216 dB (1 (.0178)(.0366) .01 dBEffective load match (.316)(.316)(.126) .024 .0366 (28.7dB)1Measurement uncertainty 1 (.006 .0005 .0028) 1 .0093(.0366)(.891)(.0178)(.891) .0005 0.08 dB(.0366)(.158) .006(.158)(.0178) .0028(.158)(.0178) .0028Total measurementuncertainty:0.22 .02 0.24 dBTotal measurementuncertainty:0.01 .08 0.09 dBNetwork Analyzer BasicsNetwork Analyzer BasicsCalculating Measurement Uncertainty After aTwo-Port CalibrationDUT1 dB loss (.891)16 dB RL (.158)Corrected error terms:(8753ES 1.3-3 GHz Type-N)DirectivitySource matchLoad matchRefl. trackingTrans. trackingIsolation 47 dB 36 dB 47 dB .019 dB .026 dB 100 dBResponse versus Two-Port CalibrationMeasuring filter insertion lossCH1 S21&M log MAGCH2 MEM log MAGReflection uncertainty1 dB/1 dB/REF 0 dBREF 0 dBCorAfter two-port calibrationS11m S11a ( ED S11a 2 ES S21a S12a EL S11a (1 ERT )) 0158. (.0045 0158. 2 *.0158 0891. 2 *.0045 0158. *.0022)After response calibration 0.158 .0088 16 dB 0.53 dB, -0.44 dB (worst-case)Transmission uncertaintyS21m S21a S21a ( E I / S21a S11a E S S21a S12a E S E L S22a E L (1 ETT )) 0891. 0891. (10 6 / 0.891 0158. *.0158 0.8912 *.0158*.0045 0158. *.0045 .003)x2 1 0.891 .0056 1 dB 0.05 dB (worst-case)Network Analyzer Basics 2STOP 6 000.000 MHzSTART 2 000.000 MHzNetwork Analyzer BasicsECal: Electronic Calibration (85060/90 series) UncorrectedCorVariety of modules cover 30 kHz to 26.5 GHzSix connector types available (50 Ω and 75Ω)Single-connectionreduces calibration timemakes calibrations easy to performminimizes wear on cables and standardseliminates operator errorsHighly repeatable temperature-compensatedterminations provide excellent accuracyAdapter Considerationsreflection fromadapterleakage signal desired signalρmeasured Directivity ρadapter ρDUTCoupler directivity 40 dB85093AElectronic Calibration Module30 kHz - 6 GHz AdapterDUTTerminationDUT has SMA (f) connectors Worst-caseSystem Directivity 28 dBMicrowave modules use atransmission line shunted byPIN-diode switches in variouscombinations17 dB14 dBNetwork Analyzer BasicsNetwork Analyzer Basics12APC-7 calibration done hereAdapting from APC-7 to SMA(m)APC-7 to SMA (m)SWR:1.06APC-7 to N (f) N (m) to SMA (m)SWR:1.05SWR:1.25APC-7 to N (m) N (f) to SMA (f) SMA (m) to (m)SWR:1.05SWR:1.25SWR:1.15

Network Analyzer BasicsCalibrating Non-Insertable DevicesSwap Equal Adapters MethodWhen doing a through cal, normally test ports mate directly cables can be connected directly without an adapter result is a zero-length throughWhat is an insertable device? has same type of connector, but different sex on each port has same type of sexless connector on each port (e.g. APC-7)What is a non-insertable device? one that cannot be inserted in place of a zero-length through has same connectors on each port (type and sex) has different type of connector on each port(e.g.,DUTwaveguide on one port, coaxial on the other)What calibration choices do I have for non-insertable devices? use an uncharacterized through adapter use a characterized through adapter (modify cal-kit definition) swap equal adapters adapter removalPort 1Port 1Port 1Port 1Network Analyzer Basics Port 1Calibration is very accurate and traceableIn firmware of 8753, 8720 and 8510 seriesAlso accomplished with ECal modules (85060/90)Uses adapter with same connectors as DUTMust specify electrical length of adapter to within1/4 wavelength of highest frequency (to avoidphase ambiguity)CalAdapterPort 1CalAdapterAdapterBPort 2AdapterBPort 2DUTPort 22. Reflection cal using adapter B.AdapterBPort 23. Measure DUT using adapter B.We know about Short-Open-Load-Thru (SOLT) calibration.What is TRL? A two-port calibration technique Good for noncoaxial environments (waveguide, fixtures, wafer probing) Uses the same 12-term error model as the more common SOLT cal Uses practical calibration standards that are easily fabricated andcharacterized Two variations: TRL (requires 4 receivers)and TRL* (only three receivers needed) Other variations: Line-Reflect-Match (LRM), Thru-Reflect-Match (TRM),plus many othersTRL was developed for non-coaxialmicrowave measurementsPo

Network Analyzer Basics 3 Network Analyzer Basics Transmission Line Terminated with Short, Open Zs Zo Vrefl Vinc For reflection, a transmission line terminated in a short or open reflects all power back to source In-phase (0 o) for open, out-of-phase (180o) for short Network Analyzer Basics Transmission Line Terminated with 25 Ω Vrefl .File Size: 2MBPage Count: 19