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摘要I摘要短波信道具有时变，多径，快速衰落等多种特点，使得接收到的短波信号存在严重的符号间干扰（Inter-symbolInterference,ISI），这种干扰会导致通信的错误或者严重失效。信道均衡是抑制ISI的关键技术之一，特别是在复杂多变的短波系统中，对于高性能的均衡算法的研究就更加重要。优化均衡算法具有很高的复杂度，一般而言，它是随延迟符号数成指数上升的。而一般的均衡器往往伴有很大的性能失真。近年来，迭代均衡算法作为抵抗ISI的有效实现方式，能获得误码性能及其实现复杂度的优化折中。根据短波系统的特点，本文在经典短波Watterson信道基础上，针对特定的短波通信技术标准，即MIL-STD-188-110C中的单音道串行模式，重点研究了RLS自适应均衡算法。利用递归最小二乘法（RecursiveLeastSquares，RLS）估计、跟踪时变短波信道系数。并在经典的Watterson信道下，基于MIL-STD-188-110C标准的单音道串行波形设计方案，给出了基于RLS算法的自适应均衡器的BER性能。通过对MIL-STD-188-110C中的单音道通信模式的仿真，分析了在Watterson信道下长交织和短交织对于系统性能的影响，对后续研究打下基础。关键词：短波系统，MIL-STD-188-110C标准，Watterson信道，RLS均衡，ISI。ABSTRACTIIABSTRACTShort-wavesystemisatime-varying,multipath,fadingsystem,thesecharacteristicswillmakethesignalaseriousinter-symbolinterference(ISI),suchinterferencecancausecommunicationerrors,evencommunicationfailure.ChannelequalizationisoneofthekeytechnologiesofeliminatingISI,thehigh-performanceequalizationalgorithmisevenmoreimportantinthevolatileshort-wavesystem.buttheoptimizedalgorithmoftheequalizationhavehighcomplexity,ingeneral,thecomplexityincreasedbytheexponentiallyofthedelaysymbols.Lowcomplexityequalizerisoftenassociatedwiththedistortionofperformance.Inrecentyears,iterativeequalizationalgorithmisaneffectivewaytoachievearesistanceISIwhichcanobtainthetrade-offsoftheBERperformanceandthecomplexityoftheoptimization.Accordingtothecharacteristicsofshort-wavesystems,intheclassicshortWattersonchannel,thispaperbasedonthespecificshort-wavecommunicationstechnologystandard,thatMIL-STD-188-110C,focusontheRLSadaptiveequalizationalgorithm.ThispaperuserecursiveleastsquaresAlgorithm(RecursiveLeastSquares,RLS)toestimate,andtrackthetime-varyingcoefficientsofHFchannel.WegiveBERperformanceofRLSundertheserialmodeinMIL-STD-188-110C.Finally,throughthemodesimulationofserial(single-tone)modeinMIL-STD-188-110C,thispapercarefullyanalysedtheperformanceofdifferentinterleavinginfluenceforfurtherresearch.Keywords:short-wavesystems,MIL-STD-188-110C,Wattersonchannel,RLSEqualizer,ISI。目录III目录第1章绪论........................................................................................................................................11.1研究背景................................................................................................................................11.1.1MIL-STD-188-110系列标准介绍.............................................................................11.1.2MIL-STD-188-110C....................................................................................................11.2短波系统...............................................................................................................................21.2.1短波传播方式.............................................................................................................31.2.2短波系统物理特点.....................................................................................................31.2.3短波系统传输特点.....................................................................................................41.3均衡技术的发展....................................................................................................................61.4本文研究的主要内容............................................................................................................71.5本文内容安排........................................................................................................................7第2章MIL-STD-188-110C系统波形方案......................................................................................92.1110C波形相关参数...............................................................................................................92.2编码.....................................................................................................................................102.3交织.....................................................................................................................................122.2.1交织写入...................................................................................................................122.2.2交织获取....................................................................................................................132.4格雷编码..............................................................................................................................142.5符号形成.............................................................................................................................152.5.1未知数据符号的形成...............................................................................................152.5.2已知符号的形成.......................................................................................................162.5.3同步前导序列...........................................................................................................162.6加扰......................................................................................................................................182.6.1随机序列发生器........................................................................................................182.7PSK调制.....