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英文资料及中文翻译DIGITALCOMMUNICATIONSYSTEMFORMODERNPEOPLE,IFYOUDONOTKNOW“DIGITALCOMMUNICATION”OR“DIGITALSIGNAL”,ITISSEEMTOBEOUTDATED,EVENWOULDBELAUGHEDAS“AIGNORANTMEN”WELLTHEN,WHATISTHE“DIGITALCOMMUNICATION”ANDWHATISTHE“DIGITALSIGNAL”THISTEXTISTODOANGENERALIZEINTHEWAYOFBRIEFANDPLAIN1、WHYDIGITALWHYARECOMMUNICATIONSYSTEM，MILITARYANDCOMMERCIALALIKE，“GOINGDIGITAL”THEPRIMARYADVANTAGEISTHEEASEWITHWHICHDIGITALSIGNALS，COMPAREDWITHANALOGSIGNALS，AREREGENERATEDFIGURE1ILLUSTRATESANIDEALBINARYDIGITALPULSEPROPAGATINGALONGATRANSMISSIONLINETHESHAPEOFTHEWAVEFORMISAFFECTEDBYTWOBASICMECHANISMS1ASALLTRANSMISSIONLINESANDCIRCUITSHAVESOMENONIDEALFREQUENCETRANSFERFUNCTION，THEREISADISTORTINGEFFECTONTHEIDEALANDPULSE；AND2UNWANTEDELECTRICALNOISEOROTHERINTERFERENCEFURTHERDISTORTSTHEPULSEWAVEFORMBOTHOFTHESEMECHANISMSCAUSETHEPULSESHAPETODEGRADEASAFUNCTIONOFLINELENGE，ASSHOWNINFIGURE1DURINGTHETIMETHATTHETRANSMITTEDPULSECANSTILLBERELIABLYIDENTIFIEDBEFOREITISDEGRADEDTOANAMBIGUOUSSTATE，THEPULSEISAMPLIFIEDBYADIGITALAMPLIFIERTHAT
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