141A信号盲解调算法研究

摘要

For meeting the demand for blind demodulation of MIL⁃STD⁃188⁃141A( 141A) signal,the algorithm of Frequency Index based Sliding⁃window Fast Fourier Transform( FFT) is improved based on the analysis of the merits and demerits of existing algorithms. The exact frequency deviation is calculated using Discrete⁃time Fourier Transform( DTFT) ,and then the preprocessing of signal calibra⁃tion is conducted based on the information of frequency deviation,and the statistic data for these frequency indexes of 141A signal are gathered.The calibrated signals can then be demodulated using the algorithm of Frequency Index based Sliding⁃window FFT.The simula⁃tion of improved algorithm shows that the improved algorithm can adjust to larger frequency deviation and has better demodulation result compared with original algorithm.%针对非协作通信中MIL⁃STD⁃188⁃141A （141A）信号盲解调的需求，在分析总结现有几种解调算法优缺点的基础上，对基于频号信息的滑动快速傅里叶变换（ Fast Fourier Transform ， FFT）解调算法提出了改进，应用离散时间傅里叶变换（ Discrete Time Fourier Transform， DTFT）算法计算信号精细频偏对信号进行校频预处理，统计获取141A信号的实际频号信息。对校频预处理后的信号应用基于实际频号信息的滑动FFT解调算法进行解调。应用仿真信号对改进的解调算法进行仿真，仿真结果表明，改进的解调算法相比原解调算法能够适应更大的信号频偏，解调效果良好。