大动态PCM/FM遥测信号的非相干解调  

Non-coherent Demodulations for Large Dynamic PCM/FM Telemetry Signal

作　　者：谢顺钦 王世练[2] 杨春[1] 

机构地区：[1]中国工程物理研究院电子工程研究所,四川绵阳621900 [2]国防科技大学电子科学与工程学院,长沙410073

出　　处：《电讯技术》2013年第11期1428-1434,共7页Telecommunication Engineering

基　　金：国家自然科学基金-中物院NASF联合基金项目(10876103)~~

摘　　要：针对大动态低码率PCM/FM遥测信号的可靠接收问题展开研究,给出了一种基于连续相位调制(CPM)信号原理的载波频偏矫正及差分序列检测的非相干接收方案。针对限幅鉴频、多符号检测及差分序列检测等3种非相干解调算法,介绍了各自应用于PCM/FM信号的算法原理,并比较了3种算法的解调性能及对大动态环境的适应能力。计算机仿真表明,在无残留频偏情况下,2符号相位差分序列检测性能最好;但在0.05倍码速率的残留频偏下,1符号相位差分序列检测的性能更好,优于2符号相位差分序列检测、限幅鉴频检测和多符号非相干检测。对PCM/FM信号的讨论包含了几种典型的非相干解调,对大动态环境下的PCM/FM接收有重要的参考价值。Reliable receptions for pulse-code modulation/frequency modulation （PCM/FM） telemetry sig-nal with low-bit-rate in large dynamic conditions are studied. A non-coherent scheme based on continu-ous phase modulation （CPM） principles is proposed, which includes the correction of carrier frequency offset and differential phase sequence detection by Viterbi algorithm. Principles of three types of non-co-herent demodulations for PCM/FM, i.e. limited-discriminator detection, multiple-symbol detection and differential phase sequence detection, are discussed. Their detection performances and adaptabilities to large dynamic conditions are compared as well. Computer simulations show that the sequence detection for 2-symbol phase difference performs the best when without residual Doppler frequency offset. While with a frequency offset of 0.05 times of symbol rate, the sequence detection for 1-symbol phase difference is bet-ter than that for the 2-symbol phase difference, and also better than the other two methods. The discus-sions about PCM/FM signal include three typical non-coherent demodulations, which are important refer-ences to the receptions of PCM/FM signal in large dynamic conditions.

关 键 词：PCM FM 大动态 非相干解调 差分解调 

分 类 号：TN927[电子电信—通信与信息系统] TN763[电子电信—信息与通信工程]