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1、摘要多用戶檢測技術(shù)是第三代移動通信系統(tǒng)關(guān)鍵技術(shù)之一。其主要思想是充分利用所有用戶的信息對接收信號做聯(lián)合檢測,抑制多址干擾,緩解“遠(yuǎn)一近”效應(yīng),從而有效地提高系統(tǒng)容量。本文對多用戶檢測技術(shù)進(jìn)行了初步的研究,并提出了幾種新的性能優(yōu)良的多用戶檢測器,主要內(nèi)容如下。提出了一種用于CDMA系統(tǒng)上行鏈路的自適應(yīng)檢測器,具有了實時性,無需訓(xùn)『練序列,且無需進(jìn)行大型互相關(guān)矩陣的求逆運(yùn)算,其檢測效果與解相關(guān)檢測器等價。該檢測器還可用來進(jìn)行幅度估計。構(gòu)造了一種抗“遠(yuǎn)一近”效應(yīng)的半盲自適應(yīng)檢測器,其檢測性能比非盲的檢測器和純盲的檢測器都有所提高。并且提出了一種分組決策反饋半盲檢測器,可以降低
2、檢測時延。另外,還提出了一種差分編碼決策指導(dǎo)(DCDD)盲去相位模糊的方法,并構(gòu)造了一種新的多徑衰落信道下的盲自適應(yīng)檢測器。該檢測器無需訓(xùn)練序列,與同類型的基于kalman濾波的去相關(guān)自適應(yīng)RAKE接收機(jī)相比,運(yùn)算量小,檢測精度高。本文的工作得到了國家自然科學(xué)基金(No.60073053,60133010)的資助。關(guān)鍵詞:多用戶檢測自適應(yīng)檢測幅度估計半盲檢測器盲去相位模糊ABSTRACTMutiluserdetectionisoneofthekeytechniquesinthe3Gmobilecommunicationsystems.Themainideabehindi
3、tistomakejointdetectiononthereceivedsignalsbymakingfullUSeoftheinformationofalltheusers’signals,whicheliminatesthemultipleaccessinterference(MAI)andrelaxesthe‘near-far’effect,andconsequentlyincreasesthecapacityofthesystem.Themultiuserdetectionisstudiedinthispaper,andseveralnovelmultiuser
4、detectorswithexcellentperformancearegivenasfollows.AnewadaptivedetectorforuplinkintheCDMAsystemisgiven,withneitherthetrainingsequencesnorthecomputationoftheinvertofcomplexbigco.elationmatrixneeded,andtheperformanceofitisequaltothatofthedecorrelatingdetector.Moreover,itcallbeusedtoestimat
5、etheamplitudesofthesignals.Anovelnear-farresistantsemi-blindadaptivemulfiuserdetectorispresentedandthedetectionperformanceofitisimprovedcomparingwiththeblindandnon·blinddetectors.Meanwhile,agroupdecisionfeedbacksemi-blindadaptivemultiuserdetectorisgivenwhichreducesthedetectiondelays.More
6、over,anovelmethodtoeliminatethephaseillegibility、Ⅳi血differentialcodeddecisiondirectionisprovided,andanewblindadaptivedetectoroverfrequency-selectivefadingchannelsisgiven.ThedetectorCanworkwithouttrainingsequences,anditscomputationalcomplexityisreducedandtheprecisionisimprovedcomparingwit
7、htheblindadaptivedecorrelatingRAKEreceiverbasedontheKalmanfilter.ThispaperissupportedbyTheNationalNaturalScienceFoundationofChina(No.60073053,60133010).Keyword:MultiuserdetectionAdaptivedeteefionAmplitudeestimationSemi-blinddetectorB吐ndphaseillegibilityelimination創(chuàng)新性聲明Y58