二次调制信号与PSK类信号的自动盲识别算法

研究了卫星通信中常用的二次调制信号和PSK类信号的自动盲识别算法。从信号时域和频域出发,提取了能反映调制方式差异的瞬时特征,并对这些特征进行了理论分析。在区分非恒包络信号时,引入了自相关处理,改进后瞬时幅度包络特征差异更加明显,在对二次调制信号进行识别时,引入了FM盲解调用于恢复内调制信号,内调制PSK信号的识别采用基于谱线特征的识别算法。最后通过计算机仿真验证了其识别性能,在信噪比不低于4 dB时,对信号集内的信号识别率达到90%以上。

An algorithm for automatic blind recognition of secondary modulation signals and PSK class signals

An algorithm is proposed for automatic blind recognition of secondary modulation signals and PSK class signals used in satellite communication. From the time domain and frequency domain of signal,the paper extracts some instantaneous characteristics which can reflect differences of modulation mode and analyzes these characteristics in theory.In distinguishing the non-constant envelope signals, the autocorrelation processing is introduced,and the improved instantaneous amplitude envelope characteristic differences become more apparent.In recognition of the secondary modulation signals,the FM blind demodulation is introduced to recover inner modulation signal, the inner PSK modulation signal is recognized by the algorithm based on spectral characteristics.Finally,the recognition performance is verified through computer simulation,when SNR is not lower than 4dB,the signal recognition rate within signal set achieves above 90%.