GPS接收机基带信号处理的研究和设计

上海交通大学硕士学位论文GPS接收机基带信号处理的研究和设计姓名：陈涛申请学位级别：硕士专业：电路与系统指导教师：毛志刚;谢憬20090101IVGPSGPSGPSMatlabMatlabSimulinkGPSGPS12CORDICarctanDCO3MatlabGPS,XilinxVertex-4GPSFPGAVResearchandDesignofGPSReceiverBasebandProcessingABSTRACTGlobalPositioningSystemisconsideredasthemostimportantpositionnavigationandtimingdevelopment.ThekeyofGPSapplicationisthereceivedevice–basebandprocessingunit,includingtwoparts:acquisitionandtrackingloop.Theresearchfocusonrealtimebasebandsignalprocessingalgorithmsandhardwarerealization.ThispaperrealizedtheGPSsoftwarereceiveronMatlabplatform.TheacquisitionofGPSsignalindividuallyemploystimedomainserialsearchandfrequencydomainparallelsearchbyFFTalgorithm.AnalysisresultshowsthatfrequencydomainacquisitionbyFFTalgorithmhasamuchlesscomputationload.Non-correlatedDLLandPLLareusedintheGPSsignaltracking.Bycomparingthespeedandhardwarecomplexity,thisdesignusingthefollowingscheme:1)TheacquisitionusesfrequencydomainparallelsearchbyFFTalgorithm,averagesampledschemeandnovelpeaksearchcircuit.2)ThearctanphasedetectorbasedCORDICalgorithmisusedincarriertrackingloopandasimplelogictoreplacethecomplexloop-uptabletoachievecarrierDCO.3)Codetrackingloopisbasedonblockadjustmentstrategywhenlocalgeneratedcodeisnotmatchinputsignal,byadjustingtheinputsignaltobettermatchthelocalcode.Toverifythedesign,sourcedatasaregeneratedinMatlabusingtheGPSmodulationway.ThedesignisimplementedonXilinxVirtex-4FPGAandtheresultshowsthedesigniscorrect.KeywordsGPSBasebandProcessingAcquisitionTrackingFPGAIX2-1GPS..........................................................................................62-2m....................................................................................72-3C/A...............................................................................................82-4...........................................................................................82-5...........................................................................122-6GPS......................................................................133-1................................................................163-2C/A.................................................................................183-3...........................................................................203-425...........................................................213-5C/A..............................................................................223-6I/Q......................................................................................223-7.........................................................................................243-8IQ....................273-919.......................................................................................284-1..................................................................................294-2................................................................................................304-3.....................................................................................304-4FFT..........................................................................324-5............................................................................................334-66............................................................................334-7.........................................................................................344-8....................................................................354-9FFTMatlab......................................375-1..................................................................................405-2DCO........................................................................................415-3DCOI&Q..........................................435-4DCO.....................................................................445-5..................................................................................465-6..................................................................................465-7.........................................................................................465-8arctan......................................................................................495-9add_sub.......................................................................................506-1.........................................................536-2.........................................................546-35.714MHzC/A.........................................................556-4Matlab5.714MHzC/A..............................566-5100ns........................................576-6.......................................................................576-7..................................................58X3-1.......................................................................163-2C/A..........................................................................173-3....................................................................173-4............................................................................