software_receiver

《software_receiver》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、DESIGNOFASINGLEFREQUENCYGPSSOFTWARERECEIVERPeterRinderNicolajBertelsenPeterRinderBasicGPSreceiverstructure-Designandimplementation2ProjectGoalDesignandimplementasinglefrequencyGPSsoftwarereceiver3GPSsignalsNavigationdataPseudo-randomnoisesequencesCarrierwave

2、4NavigationdataSatelliteorbitinformation(ephemerides)SatelliteclockinformationSatellitehealthandaccuracySatelliteorbitinformation(almanac)Bit-rateof50bpsRepeatedevery12.5minutes5Pseudo-randomnoisesequencesSpreadingsequences(C/A)Lengthof1023chipsChippingrateo

3、f1.023Mcps1sequencelasts1ms32sequencestoGPSsatellitesSatelliteidentificationSeparatesignalsfromdifferentsatellites6CarrierwaveSignaltransmissionTwofrequencies:L1=1575.42MHzL2=1227.60MHzC/AcodeonL1Bipolarphase-shiftkeying(BPSK)modulation7GPSsignalCarrierwaveN

4、avigationdataCarrieranddata20ms1ms1databit8GPSsignalCarrieranddataResultingsignalPRNcode9ImportanttasksofaGPSreceiverPreparereceivedsignalsforsignalprocessingFindsatellitesvisibletothereceiverForeachsatelliteFindcoarsevaluesforC/Acodephaseandcarrierfrequency

5、FindfinevaluesforC/AcodephaseandcarrierfrequencyKeeptrackoftheC/AcodephaseandcarrierfrequencyastheychangeovertimeObtainnavigationdatabitsDecodenavigationdatabitsCalculatesatellitepositionCalculatepseudorangeCalculateposition10ReceiverchannelReceiverchannelRe

6、ceiverchannelReceiverchannelReceiverchannelReceiverchannelReceiverchannelReceiveroverviewRFfront-endA/DconverterAcquisitionReceiverchannelPositioncalculationPreparereceivedsignalsforsignalprocessing11ReceiverchannelReceiverchannelReceiverchannelReceiverchann

7、elReceiverchannelReceiverchannelReceiverchannelReceiveroverviewRFfront-endA/DconverterAcquisitionReceiverchannelPositioncalculationFindsatellitesvisibletothereceiverFindcoarsevaluesforC/Acodephaseandcarrierfrequencyforeachsatellite12ReceiveroverviewFindfine

8、valueforC/AcodephaseFindfinevalueforcarrierfrequencyKeeptrackoftheC/AcodephaseandcarrierfrequencyastheychangeovertimeCodetrackingCarrierTrackingBitsyn-chronizationDecodenav.dataCalculatesatelli