PCM/FM遥测信号软件解调算法研究

Research onSsoftware demodulation algorithm ofSPCM/FM signal

摘要:

针对目前航天测控中PCM/FM遥测系统使用的调频非相干解调技术存在解调门限较高的问题,研究一种基于最大似然思想的多符号检测(Multi-Symbol Detection, MSD)解调方法。介绍多符号检测原理,并针对以往同步方法的不足,研究一种将码元判决过程与同步相结合的变步长同步方法。仿真和测试结果表明,基于MSD解调PCM/FM信号是一种非常有效的方法。对下一代遥测信号解调系统的研制具有重要的应用价值。

Abstract:

Aimed at theSproblem that theSdemodulation threshold ofSnon-coherent demodulation technologySof PCM/FM telemetry system using frequency modulation inStheSpresent situation of aerospace measurement and controlSis higher,Sresearch a kind of multiple symbol detection based on maximum likelihood thought (Multi - Symbol Detection, MSD) demodulation method. This paper introduces the principle of multiple symbol detection and aiming at the shortcomings of the previous synchronization method, studies a kind of symbol decision process and synchronization of the combination of synchronization method. Simulation and test results show that based on MSD demodulation PCM/FM signal is a very effective method. For the development of the next generation of remote sensing signal demodulation system has important application value.