外文翻译---数据采集：简介

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1、附录A英文文献原文DataAcquisition:AnIntroductionBruxtonCorporationThisisaninformalintroductiondigitaldataacquisitionhardware.ItisprimarilydirectedtowardsassistingintheselectionofappropriatehardwareforrecordingwiththeAcquireprogram.OverviewInprinciple,dataacquisitionhardwareisquitesimple.AnA/Dconver

2、terdeliversasequenceofvaluesrepresentingananalogsignaltoanacquisitionprogram.Inpractice,selectingandproperlyusingdataacquisitionhardwareismorecomplex.Thisdocumentprovidesaninformalintroductiontothetopic..Manyoftheexamplesaretakenfrompatch-clamprecording.Thistechniquerequiresaccurateacquisi

3、tionoflow-levelsignals(picoamperes)withbandwidthintheaudiorange(upto10kHz).BackgroundAdataacquisitionsystemconvertsasignalderivedfromasensorintoasequenceofdigitalvalues.Thesensorisconnectedtoanamplifier,whichconvertsthesignalintoapotential.Theamplifierisinturnconnectedtoadigitizer,whichcon

4、tainsanA/Dconverter.Thedigitizerproducesasequenceofvaluesrepresentingthesignal.SignalSourceThesourceofmostsignalstobedigitizedisasensor,connectedtoanamplifierwithappropriatesignalconditioning.Theamplifierdeliversanelectricalsignal.ThissignalisthendigitizedusinganA/Dconverter.Forpatch-clamp

5、recording,thesensorsaresolutionfilledpipettes.Thepipetteisconnectedtoapatch-clampamplifierthatconvertsthevoltageatthepipetteorthecurrentthroughthepipettetoahigh-levelsignal.Byconvention,thefull-scaleoutputrangeofapatch-clampamplifieris±10V,matchingtherangeofcommoninstrumentationqualitydigi

6、tizers.DigitizerAdigitizerconvertsoneormorechannelsofanalogsignaltoasequenceofcorrespondingdigitalvalues.TheheartofadigitizerisanA/Dconverter,adevicethatsamplesananalogsignalandconvertsthesampletoadigitalvalue.Forexample,forrecordingfromasingleionchannel,thedigitizermightdeterminetheoutput

7、ofthepatchclampamplifieronceevery50msandprovidetheresultingvaluetothecomputer.SamplingTheoremThepurposeofdataacquisitionistoanalyzeananalogsignalindigitalform.Forthistobepossible,thesequenceofvaluesproducedbyadigitizermustrepresenttheoriginalanalogsignal.Thesa