GPS信号中M码的设计与实现

沈阳理工大学学士学位论文I摘要全球定位系统(GPS)是新一代的精密卫星导航定位系统。由于其全球性、全天候以及连续实时三维定位等特点，在军事和民用领域得到了广泛的发展。随着现代化通信技术的发展，对导航要求愈加精确，抗干扰能力越高，因此设计出了新的GPSM码信号。新的M码信号要求有效地同传统信号分离，减小信号的相互干扰，并且具有良好的抗多径效应的能力，因此产用新的调制方式(BOC调制)，而非BPSK。本文在论述了GPS系统架构及其相关原理上，对M码信号产生与调制进行了研究，建立了信号产生模型，并以MATLAB为仿真平台，完成了信号的调制仿真，并进行了详细的结果分析。对比传统信号得到M码信号的优势，完成了设计要求。关键词：GPS；M码信号；BOC调制；仿真沈阳理工大学学士学位论文IIAbstractAsthenewgenerationofthesatellitenavigationsystems,globalpositioningsystem(GPS)hasbecomeawidelyusedsystem.Duetoglobosity,all-weatherandcontinuumrealtimethree—dimensionalorientation,ithasbeenwidelydevelopedinthefieldsofmilitaryandcivilaviation.McodesignalplaysallimportantroleinGPSmodernizationandisthemainanti·countermeasuretobeimplementedintheGPSsystem.NewMcodesignalrequirementswithtraditionalsignalseparationeffectively,reducethesignalinterference,andhasagoodabilitytoresistmultipatheffect,sotheproductionwiththenew(BOCmodulation)modulationway,insteadofBPSK.GPSsystemarchitectureanditsrelatedinthispaperdiscussestheprinciple,studiedtheMcodesignalandmodulating,signalmodelisestablished,andbasedonMATLABsimulationplatform,completedthemodulationofsignalsimulation,andhascarriedonthedetailedanalysisoftheresults.ComparedwithtraditionalsignaltogettheadvantageoftheMcodesignal,completedthedesignrequirements.Keywords：GPS；Mcodesignal；BOCmodulation；simulation沈阳理工大学学士学位论文III目录1绪论.........................................................................................................................................11.1GPS信号概述...............................................................................................................11.2MATLAB简介..............................................................................................................32GPS系统及信号.....................................................................................................................52.1GPS系统架构...............................................................................................................52.1.1空间段..............................................................................................................52.1.2控制段................................................................................................................62.1.3用户段................................................................................................................72.2GPS信号介绍...............................................................................................................82.2.1GPS卫星信号产生.............................................................................................82.2.2导航电文............................................................................................................92.2.3PRN码的产生..................................................................................................113M码信号产生.......................................................................................................................173.1GPSM码信号产生原理............................................................................................173.2BOC调制特性分析....................................................................................................173.2.1BOC调制信号的产生......................................................................................173.2.2BOC调制信号的功率谱..................................................................................193.2.3BOC调制信号的自相关特性..........................................................................213.3BOC调制信号的优势................................................................................................214M码信号的设计与实现.......................................................................................................234.1总体设计方案............................................................................................................234.2总体设计参数............................................................................................................234.3设计流程图................................................................................................................244.4仿真结果及分析........................................................................................................25结论........................................................................................................................................27致谢........................................................................................................................................28参考文献..................................................................................................................................29附录A英文原文..................................................................................................................30沈阳理工大学学士学位论文IV附录B汉语翻译..................................................................................................................37附录C程序代码..................................................................................................................42沈阳理工大学学士学位论文11绪论1.1GPS信号概述人造地球卫星的出现使古老的无线电信标导航迈向了太空，实现了全球覆盖、全天候工作、实时高精度定位等一