标签: max1471

Inaremotekeylessentry(RKE)systemacarisunlockedfromadistancebyaradiocodesentfromakeyfobtoareceiverinthecar.RKEsystemsusuallyoperateatfrequenciesintheunlicensedISMbandthatincludes315MHzand433.92MHz.Withtheadventofremotestartingfeaturesandtwo-wayRKEwithverification,designerswanttoincreasetheusablerangeoftheseshort-rangedevices.ReplacingSAWresonatortransmitterswithhigh-frequency,tolerancephase-locked-looptransmittersallowsreceiverswithnarrowerbandwidthtobeused.RFICreceiverstakeadvantageofthesenarrowerbandwidthstoimprovesensitivity,whichinturnincreasestheusablerange.Oncethetransmittedpowerandthereceiversensitivityareestablished,thepathlossofthesignalfromtransmittertoreceiveristhemaindeterminationofusablerange.Thisapplicationnotedescribeshowpathlossisaffectedbythegroundbounceoftheradiosignalandgivesasimplifiedapproximateequationforpathloss.Graphspredictpathlossasafunctionofdistanceinanemptyparkinglot.Finally,thenoteoffersguidelinesforpredictingtheeffectsofmultipathsignalsandblockage.……

移键控（ASK）和小康键控（OOK）接收器，用于间歇性低数据速率应用的RKE，安全回家，车库门开启装置，远程控制等。来从远程发射机的ASK或OOK接收的数据，在数据切片重建。数据切片，因此，一个组成部分，ASK和FSK接收机在260MHz到470MHz短距离UHF波段操作下的FCCPart15.231规则。本应用笔记介绍Maxim的UHF接收机，包括对MAX1470，MAX1473，MAX1471，MAX7030和MAX7032的像收发数据切片的运作。Maxim>AppNotes>BASESTATIONS/WIRELESSINFRASTRUCTUREWIRELESS,RF,ANDCABLEKeywords:amplitude-shiftkeying,ASK,On-OffKeying,OOK,RKE,dataslicers,FSK,short-rangeUHFband,260MHz,Dec22,2005470MHz,MAX1470,max1473,max1471,max7030,max7032,demodulatedASKsignalAPPLICATIONNOTE3671DataSlicingTechniquesforUHFASKReceiversAbstract:Amplitude-shiftkeying(ASK)andon-offkeying(OOK)receiversareusedforintermittentlow-data-rateapplicationslikeRKE,homesecurity,garage-dooropeners,andremotecontrols.ThedatathatcomestoanASKorOOKreceiverfromaremotetransmitterisreconstructedinthedataslicer.Thedatasliceris,therefore,anintegralpartofASKandFSKreceiversthatoperateinthe260MHzto470MHzshort-rangeUHFban……

Amplitude-shiftkeying(ASK)andon-offkeying(OOK)receiversareusedforintermittentlow-data-rateapplicationslikeRKE,homesecurity,garage-dooropeners,andremotecontrols.ThedatathatcomestoanASKorOOKreceiverfromaremotetransmitterisreconstructedinthedataslicer.Thedatasliceris,therefore,anintegralpartofASKandFSKreceiversthatoperateinthe260MHzto470MHzshort-rangeUHFbandundertherulesofFCCPart15.231.ThisapplicationnoteexplainstheoperationofthedataslicersfoundinMaxim'sUHFreceivers,includingtheMAX1470,MAX1473,andMAX1471,andtransceiversliketheMAX7030andMAX7032.……