预览加载中，请您耐心等待几秒...

APSK信号载波相位的精同步方法(英文).docx

预览
1/3
2/3
3/3

在线预览结束，喜欢就下载吧，查找使用更方便

下载提示 文本预览

如果您无法下载资料，请参考说明：

1、部分资料下载需要金币，请确保您的账户上有足够的金币

2、已购买过的文档，再次下载不重复扣费

3、资料包下载后请先用软件解压，在使用对应软件打开

APSK信号载波相位的精同步方法(英文) AdvancedPhaseShiftKeying(APSK)isamodifiedversionofthetraditionalPhaseShiftKeying(PSK)modulationscheme,whichiscommonlyusedindigitalcommunicationsystems.APSKoffersseveraladvantagesoverthetraditionalPSKmodulationscheme,suchaslowererrorrate,higherspectralefficiency,andbetterpowerefficiency.However,APSKalsoposessomechallengesintermsofcarrierphasesynchronization,whichisessentialforreliablecommunication.Inthispaper,wewilldiscusssomeoftheexistingmethodsforaccuratecarrierphasesynchronizationinAPSKmodulationandwillproposeanewmethodbasedonblindphasesearchalgorithm. ExistingMethodsforCarrierPhaseSynchronizationinAPSKModulation 1.CarrierPhaseEstimationusingPilotSymbols Awidelyusedmethodforcarrierphasesynchronizationindigitalcommunicationsystemsiscarrierphaseestimationusingpilotsymbols.Inthismethod,aknownsequenceofsymbols,calledpilotsymbols,isperiodicallyinsertedintothedatastream,andthecarrierphaseisestimatedbyperformingcorrelationbetweenthereceivedpilotsymbolsandtheexpectedpilotsymbols.Theestimatedcarrierphaseisthenusedtodemodulatethedatasymbols. However,thismethodsuffersfromseveraldrawbacks,suchasreducedavailablebandwidth,increasedcomplexity,andincreasedsensitivitytonoiseandchannelimpairments. 2.ReferenceSignal-basedCarrierPhaseSynchronization Anotherapproachforcarrierphasesynchronizationisthereferencesignal-basedmethod.Inthismethod,areferencesignalwithaknowncarrierphaseistransmittedalongwiththedatasymbols.Thereceivedreferencesignalisthenusedtoestimatethecarrierphaseatthereceiver.Thismethodrequiresahigh-qualityreferencesignal,whichmaynotalwaysbeavailableinpracticalcommunicationsystems. 3.BlindCarrierPhaseSearchAlgorithm Ablindcarrierphasesearchalgorithmisaneffectivewaytoachievecarrierphasesynchronizationwithouttheneedforareferencesignalorpilotsymbols.Inthismethod,thereceiverperformsablindsearchoverarangeofpossiblecarrierphasestofindthephasethatmaximizesthesignal-to-noiseratioofthereceivedAPSKsignal.Severalblindcarrierphasesearchalgorithmshavebeenproposed,su