基于瞬时相位新特征的数字调制信号识别

Digital modulation signal recognition based onnew features of instantaneous phase

针对四相移相键控(4PSK)和八相移相键控(8PSK)难以从瞬时特征区分这一问题,本文提出了一种基于瞬时相位的特征——分段相位均值最大值。设计了一种基于瞬时特征的调制识别方案,完成了多进制数字振幅调制(MASK)(M=2、4、8),多进制数字相位调制(MPSK)(M=2、4、8)共6种数字信号的调制识别。通过对信号的非线性相位进行分段,对每一段求均值,并找出均值序列中的最大值等操作,提取了新的特征参数,完成了4PSK与8PSK的区分。理论分析与仿真结果相一致。仿真结果表明,在信噪比高于4 dB时,4PSK与8PSK调制方式的正确识别概率可以达到90%以上。

In view of the difficulty of distinguishing 4 phase shift keying(4PSK)and 8 phase shift keying(8PSK)from instantaneous phase,a new characteristic based on the instantaneous phase is proposed,namely the maximum value of segmented phase mean.A modulation recognition scheme based on instantaneous features is designed to complete the modulation recognition of six kinds of digital modulation of multiple amplitude shift keying(MASK)(M=2,4,8)and multiple phase shift keying(MPSK)(M=2,4,8).By segmenting the nonlinear phase,calculating the mean value of each segment,and finding the maximum value in the sequence,the new characteristic parameter is extracted,and 4PSK and 8PSK are distinguished.The theoretical analysis is consistent with the simulation results.The simulation results show that the correct recognition probability of 4PSK and 8PSK can reach more than 90%when the signal-to-noise ratio is higher than 4 dB.