Optoelectronic Frequency Response At 1319 nm

1 Page 1 NATLINST.OFSTAND&TECH 5urementServices: ^ fREFERENCE FUBifCAiioNs CalibrationServiceofOptoelectronic nist FrequencyResponseat1319nmfor pSbuciti^^ CombinedPhotodiode/RFPower 250-51 SensorTransferStandards PaulD.HaleandC.M... Open at page → 2 Page 2 rhe NationalInstituteofStandardsandTechnologywasestablishedin1988byCongressto"assistindustryin thedevelopmentoftechnology ...neededtoimproveproductquality,tomodernizemanufacturingprocesses, toensureproductreliability . .... Open at page → 3 Page 3 NISTSpecialPublication250-51 NISTMEASUREMENTSERVICES: CalibrationServiceofOptoelectronic FrequencyResponseat1319nmfor CombinedPhotodiode/RFPower SensorTransferStandards PaulD.HaleandC.M.Wang Optoelectronics Division Elec... Open at page → 4 Page 4 NationalInstituteofStandardsandTechnologySpecialPublication250-51 Natl.Inst.Stand.Technol.Spec.Publ.250-51,51pages(Dec.1999) CODEN:NSPUE2 U.S.GOVERNMENTPRINTINGOFFICE WASHINGTON: 1999 ForsalebytheSuperintendent ofDocumen... Open at page → 5 Page 5 Contents 1.Introduction , 1 2.Principleofheterodynefrequencyresponsemeasurements 2 2.1Photodiodewithaccesstobiasmonitor 3 2.2Combinedphotodiode/rfpowersensortransferstandard 5 3.Nd:YAGheterodynemeasurementsystem 6 3.1Bas... Open at page → 6 Page 6 AppendixA:Useoftransferstandardinaratiosystem 30 A.lApplicationofheterodyneformalismtoarbitrarymodulationdepth 30 A.2Calibrationtransferusingratiomeasurements 31 A.3Sourcesofuncertaintyinratiomeasurementsystem 33 Typeofp... Open at page → 7 Page 7 CalibrationServiceofOptoelectronicFrequencyResponseat1319nmfor CombinedPhotodiode/rfPowerSensorTransferStandards PaulD.HaleandC.M.Wang NationalInstituteofStandardsandTechnology Boulder,Colorado80303 Thisdocumentdescribes... Open at page → 8 Page 8 Inthepast,photoreceiverfrequencyresponsemeasurementshavehadhighuncertaintiesfortwo reasons:inaccurateknowledgeoftheopticalstimulusandlargeuncertaintiesinthemicrowave powermeasurement.Withcarefulattentiontosystemperforman... Open at page → 9 Page 9 whereEqisthepermittivityoffreespace,|ioisthepermeabilityoffreespace,Eistheelectric fieldvector,E*isitscomplexconjugate,andA;isaunitvectorinthedirectionofpropagation. Theheterodynebeatnoteatfrequency/isgeneratedbymixingsi... Open at page → 10 Page 10 workphasecanbeneglected.Equation(4)assumesthatthedetectorisreverse-biasedanduses theconventionofpositivecurrentflowinginthereversedirectionofthediode.Thefirsttermon therightsideisthedcphotocurrent,whichflowsthroughthebia... Open at page → 11 Page 11 rangeoffrequencies.Thispracticeassumesthatbothsystemsimpartnegligibleerroratthat frequencyandcanbemisleading. Anothermethodofcomparisonusestheabsoluteresponse. Thismethodsuffersfromconnector insertionlossreproducibilitya... Open at page → 12 Page 12 ^ T^^ ^pd^sensor\^ ' (8) wherekisthesensorcalibrationfactorandTp^andr^g„^^^arecomplexreflectioncoefficients. However,Cdoesnotneedtobeknownandthepowermeterreadingdoesnotneedtobe correctedwithafrequencydependentcalibration... Open at page → 13 Page 13 Intensitycontrol loop Intensitycontrol loop —p.tofastdetecter, J counter,andPLL 70MHzOsc DetectortoPLL (Figure4) Tospecimen,spectrum aniayzer,andoptional powermeter Figure2.Schematicofheterodynemeasurementsystem.Labeledc... Open at page → 14 Page 14 I OpticalInput FromLasers I 3dBFiber Coupler 1GHz Amplified Receiver 5GHzAmplifier 2.92(f)-2.4(m) Adapter , Adapter Input2 Input1 40GHz Detector ^nrHr 2.4(m)-3.5(f) Amplifier Adapter Counter Figure3.Frequencycountersubas... Open at page → 15 Page 15 50GHz Amplifier 1.85(m)toWR-19Adapter 62.15GHz GunnOscillator 292(p -2.4(m) Adapter 40GHz Detector ^ OpticalInput fromLasers 40-60GHzMixer 26GHz Amplifier 33GHzBandwidth CoaxialCable 40GHzRFCounter Input1 Figure4.Subasse... Open at page → 16 Page 16 Opticalsignal fromBS2 1GHzreceiver BiasT Monitor RF Synthesizedsignal generator 8dBm PLLboxdetailedinFigure6 LO RF FastOut on/off Power supply i 7 £ Manualgain adjust YAG3piezoinput 20second timeconstant YAG2 1.5X;>—^the... Open at page → 17 Page 17 ThesescanoptionsareaccessiblethroughauserinterfaceprogramcalledHETSETUP.BAS. Thisinterfaceprogramisdesignedtoberunasanexecutablewhichcallsotherprograms,alsoin compiledexecutableform,whichrunthedififerentscanoptionslisted... Open at page → 18 Page 18 LO RF topiezoand thermalcontrols Mixer ECL comparator TTLcrystal oscillator 60MHz Low-pass Filter f 55MHz ECLphase/frequency detector R2 C1R3 — 1 1— R1 AAA- TTLto ECL Low-pass Filter ALoopfilter Manualgain adjust Figure6... Open at page → 19 Page 19 goingtothefrequencymeasurementeissemblytothepowergoingtothespecimeniscontrolled byVBS3. Effectswhichcausethemodulationdepthtovaryfrom100%shouldbeminimized.Theoptical returnlossoftestdevicesshouldbehigherthan20dBtoreducem... Open at page → 20 Page 20 Table1.Summaryoftypicalfrequencyresponsemeasurementuncertaintiesforphotodiode withrfpowersensorand3dBattenuator. Sourceofuncertainty Uncertainty, A. 19/U TypeA Measurementrepeatabilitys <0.05 Offsetcorrection 0.007 Envir... Open at page → 21 Page 21 wherebisthebandwidthparameterandK{)isthekernelfunction,whichtypicallyhasthe followingproperties: 1. ^0forall ^ 2.rmdi =1 (10) J-00 3. ^(-0=A:(OforaU^. Thatis, (x)isobtainedasaweightedaverageoffrequencyresponsesaroundx.Th... Open at page → 22 Page 22 MSEix) =0.0046S5b^c^+ 0.76242 ^ where isthesecondderivativeofR^Cy)evaluatedaty=xusingasplinemethodand isthe varianceoftheresponseofagivenscan.Thisvariance,however,isunknownandneedstobe estimated.Atechnique[20]thatworkswe... Open at page → 23 Page 23 isthebetween-scanuncertaintyand £^MSEfx) i=\m (18) 22.5 24.5 1 ' I ' r 23.0 23.5 24.0 Freauencv.GHz Figure7.Dotsrepresentthemeasuredresponse, denotestheinterpolatedresponsesat requestedfrequenciesbasedonacubic splinefit,... Open at page → 24 Page 24 relativelylargeuncertainty,whiletheshapeisspecifiedwithmuchloweruncertainty.The techniquedescribedbelowisvalidforlogarithmicdataiftheoffsetsoroutliersarelessthana fewtenthsofadecibel;otherwise,thecalculationshouldbeperfo... Open at page → 25 Page 25 Theofifsetuncertaintycanbecharacterizedbythestandarddeviationofthea,If>'„ independentGaussianrandomvariables,thevarianceofthemedianof>^,, is approximatelyequalto[21] .,y,,are -Kvariy.) (25) 2k Now,byexpanding y(/) intoas... Open at page → 26 Page 26 00 D 0) 0) c o Q. </) 0 21-0.4— 0.4 0 D 0) N m-0.8— OS E v_ O c c (0 0 -1.2— 1.6 0 1 ' r 20 40 Frequency,GHz 60 1 2 3 Frequency,GHz Figure8.Meannormalizedresponseofthecheckstandardshiftedtogive0dBat0.05GHz. Uppergraphish... Open at page → 27 Page 27 ^ 0.08 f-0.04 Q-0.06 C^0.04 0 T 20 40 Frequency,GHz 60 60 1 ' 1 20 40 Frequency,GHz Figure9,Measurementsonhighbandofthecheckstandard.Topgraphshowsdeviationfromthe meanwhichneglectsmeasurementsonJuly25,1997.Bottomgraphsho... Open at page → 28 Page 28 0.04 c (0 0 E o c q CO > 0 D 0 D) (Q I 1 ' \ P^requency,GHz^ £ 0.01 0.006— 0.002— -0.002— -0.006 August4,1997 vember10,1998 j March3,1998 January1^,1998 October27.1998 December2,1997 April-June,1996 18 20 22. Temperature... Open at page → 29 Page 29 Measurementsonthehighbandphotodiodeconsistedofsweptscansoverthefollowing approximateranges:50MHzto1GHz,500MHzto40GHz,and38GHzto55GHz.Two scansweremadeinbothforwardandreversedirections,givingatotaloffourscansineach range.... Open at page → 30 Page 30 2 m (29) asthetotaltypeAuncertaintyinTable1, isobtainedusingtheoffsetadjusteddataineq(16), misthenumberofscanswithintheparticularfrequencyband,and isthemaximumofthe ^ (seeeq(27))forallthescansandfrequencybands.Ifoffsetsa... Open at page → 31 Page 31 biascurrentanda3dBpadgivesanerrorof0.013%atlowfrequencies.Thebackgroundnoise isabout-40dB(re1mW)forthermalpowersensors. Referencepoweruncertainty:Ifthetransferstandardisofthetypewherethepowersensoristo bedisconnectedtosc... Open at page → 32 Page 32 5.QualityControl 5.1Calibrationnotebook Anotebookwhichdescribesthemeasurementsetupforallcalibrations,voltagerangerangeused foreachscanandcorrespondingfrequencyrange,biasingconditions,adapters,andanyother pertinentinforma... Open at page → 33 Page 33 standarditself.Asfurthermeasurementsonthecheckstandardareacquired,theestimateof willbemodified. 5.4Futuresystemchanges Possiblefuturesystemchangescouldinclude,butarenotlimitedto,replacementofYAG2, modificationofYAG3,useo... Open at page → 34 Page 34 5.Gifford,A.D.;Humphreys,D.A.;Hale,P.D.Comparisonofphotodiodefrequency responsemeasurementsto40GHzbetweenNPLandNIST.Electron. Lett.,vol.3 1,pp. 397-398;1995. 6.Hale,P.D.;Franzen,D.L.Accuratecharacterizationofhighspeedpho... Open at page → 35 Page 35 18.Hadle,W.Smoothingtechniqueswithimplementation instatistics.NewYork:Springer- Verlag,1991. 19.Altman,N.S.Anintroductiontokernelandnearest-neighbornonparametricregression.Am. Statistician,vol.46,pp.175-185;1992. 20.Rice... Open at page → 36 Page 36 AppendixA:Useoftransferstandardinaratiosystem A.lApplicationofheterodyneformalismtoarbitrarymodulationdepth Signalsthatdonothave100%modulationdeptharecommonlyusedinoptoelectronic test equipment.Anarbitrarymodulationdepth... Open at page → 37 Page 37 powersensorarepermanentlyattachedandthecombinednormalizedresponseisfurther normalizedtogive0dBat50MHz. Inthecaseofthereceiverwithoutaccesstobiascurrent(seeAppendixD),themodulationdepth ofanunknownsourcecanbefoundintermso... Open at page → 38 Page 38 ThenormalizedresponseoftheDUTisthenfoundusingeq(A5),thedophotocurrent,andtherf power(includingaUcalibrationfactors)fromtheDUT Insometestapplications itmaybepreferabletomeasuretheDUT'sfrequencyresponseinterms ofthecouplin... Open at page → 39 Page 39 ^^^^= -JTi • (A13) "avg-.DUT A.3Sourcesofuncertaintyinratiomeasurementsystem Thefollowingisabrieflistoferrorsourcesthatmustbeconsideredwhendesigningaratiotest system. Typeofphotoreceiverspecimen:Equations(A9),(AlO),and(A... Open at page → 40 Page 40 Modulated source rfsignal generator Fiber coupler Transfer standard rfpower meter FigureAl.Ratiomeasurementsystem 34 Open at page → 41 Page 41 AppendixB:Heterodynesystemwithunequalpowers Thepowersfromeachlaserincidentonthedetectormaynotbeequal.Inthiscaseitispossible toformulatetheexpressionforthenormalizedresponseinawaythateliminateserrorfromthe assumptionthatt... Open at page → 42 Page 42 Hence,a4%fluctuationinPq2willcausea 0.04%or0.0017dBchangeinthemeasured valueof Ontheotherhand,largedifferencesbetween thelaserpowerscanleadtolargeerrorsineq (6),eveniftheindividualphotocurrentsare known.Thiserrorisshovmi... Open at page → 43 Page 43 AppendixD:Photoreceiverwithnoaccesstobiasmonitor D.lExpressionofabsoluteresponsivityintermsofmeasuredquantities Someopticalreceiverswillnotallowaccesstothedcphotocurrentorbiascurrent.Inthiscaseit isneccessarytomeasurethe... Open at page → 44 Page 44 noise.Offsetcorrectionforthefiberconnectorinsertionlossmustbeincludedtoreducethe relativeuncertaintytoanacceptablelevel.Theuncertaintyintheabsolutelevelstillremainsand cannotbecharacterizedwithinthetolerancesthataretypic... Open at page → 45 Page 45 TableDl.Summaryoftypicalfrequencyresponsemeasurementuncertaintiesfortheamplified photoreceiver(nominalbandwidthof0.8GHz)withthermalrfpowersensor. Sourceofuncertainty Uncertainty, k=1,% TypeA Measurementrepeatability@0.01... Open at page → 46 Page 46 AppendixE.Samplecalibrationcertificate U.S.DEPARTMENTOFCOMMERCE NATIONALINSTITUTEOFSTANDARDSANDTECHNOLOGY ELECTRONICSANDELECTRICALENGINEERINGLABORATORY Boulder,Colorado80303 REPORTOFCALIBRATION ReferenceReceiver XXXphoto... Open at page → 47 Page 47 Temperaturecontrol Desktop |-*- computer Dataacquisition Fast photodiode Intensity/\ controlloop D L I YAG#1 Intensity controlloop BS D 50/50 BS YAG#2 BS M 20dB RF counter Biassupplywith monitor Fast photodiode DUT RF po... Open at page → 48 Page 48 ofthedataacquisitionequipment.Atpresent,thehighestresolutionachievableinswept operationisabout300kHz.Finerresolution(<100Hz)isattainedusingaphase-lockedloop (notshowninfigure1)atfi'equenciesbetween300kHzand1GHz,Thelasers... Open at page → 49 Page 49 mismatch,andisthepowerthatwouldbedeliveredtoanidealloadR^.Measurementsare typicallymadewithtransmissionlinesandloeidswithcharacteristicimpedanceof50Q;however theseequationsalsoapplytomeasurementswith75Qsystems. Calculati... Open at page → 50 Page 50 fifthofthecustomerrequestedresolution.Fourscans(twoineachdirection)weremadeforeach fi*equencyrangewithoverlapofaboutoneormoregigahertztoverifyconsistentoperation. Measurements atspecificfi-equencieswereextractedfi*omthes... Open at page → 51 Page 51 Table1.Summaryoftypicalfrequencyresponsemeasurementuncertaintiesforphotodiode withrfpowersensorand3dBattenuator. Sourceofuncertainty Uncertainty, k=\,% TypeA Measurementrepeatabilitys <0.05 OffsetcorrectionSg 0.007 Envir... Open at page → 52 Page 52 gp'(^3)AiuiB^JGOUfi Open at page → 53 Page 53 AppendixF.Shippinginstructions Equipmentshouldbeshippedinwell-paddedfoam,orotherwisemechanical-shock insulated cases,appropriateforreshipmentbacktothecustomer.Operationinstructionsorinstruction manualsshouldbeincluded,as... Open at page → 55 Page 55 TechnicalPublications Periodical JournalofResearchoftheNationalInstituteofStandardsandTechnology—ReportsNISTresearch anddevelopment inthosedisciplinesofthephysicalandengineeringsciencesinwhichtheInstitute is active.These... Open at page → 56 Page 56 «I -3^ ° S£ a>_j=S ' ,0 Qg^2 fe 13^ .§ oa2 o^ ^Zc«ropaoa. Open at page →