常规调制信号与扩频信号的调制识别算法  

Modulation Identification Algorithm for Conventional Modulation Signals and Spread Spectrum Signals

作　　者：占锦敏 赵知劲[1,2] Zhan Jinmin;Zhao Zhijin(School of Communication Engineering, Hangzhou Dianzi University, Hangzhou,Zhejiang 310018, China;State Key Lab of Information Control Technology in Communication System, The 36Research Institute of China Electronics Technology Group Corporation, Jiaxing, Zhejiang 314001, China)

机构地区：[1]杭州电子科技大学通信工程学院,浙江杭州310018 [2]中国电子科技集团第36研究所通信系统信息控制技术国家级重点实验室,浙江嘉兴314001

出　　处：《信号处理》2020年第4期511-519,共9页Journal of Signal Processing

基　　金：国家自然科学基金资助项目(61571172)。

摘　　要：由于直扩信号(Direct Sequence Spread Spectrum,DSSS)通常淹没在噪声中,为了有效地识别直扩信号、跳频信号(Frequency Hopping Spread Spectrum,FHSS)和常规调制信号,提出基于瞬时特征和高阶累积量的识别算法。首先推导证明了FM、MFSK、MPSK、DSSS、FHSS信号的归一化四阶累积量切片c4是相同的,并推导得到AM和MQAM的c4通用公式。然后,利用归一化四阶累积量切片c4特征参数检测噪声中通信信号,利用占用带宽特征参数将信号分为扩频信号和常规调制通信信号两类;最后利用瞬时特征参数和高阶累积量特征参数,分别识别扩频信号和5种常规调制通信信号。仿真结果表明,当信噪比高于1 dB时,该算法对上述7种信号的正确识别率可达到100%。Since the direct sequence spread spectrum is usually submerged in noise,in order to effectively recognize the direct spread sequence signal,the frequency hopping spread spectrum and the conventional modulated signals,an identification algorithm based on instantaneous characteristics and high-order cumulants is proposed.Firstly,the normalized fourth-order cumulant slice parameters c4 of FM、MFSK、MPSK、DSSS and FHSS are verified the same,and the general expressions of c4 for AM and MQAM are deduced.Secondly,c4 is used to detect the communication signals in the noise.And then the occupied bandwidth characteristic parameter is used to divide the signal into two types:spread spectrum signals and conventional modulation communication signals.Finally,the parameters of instantaneous characteristic and high-order cumulants characteristics are utilized,which identify the spread spectrum signals and the five conventional modulated communication signals,respectively.The simulation results show that when the signal-to-noise ratio is higher than 1 dB,the correct recognition rate of the above seven kinds of signals can reach 100%.

关 键 词：瞬时特征参数 高阶累积量 决策树分类器 调制信号识别 

分 类 号：TN911.3[电子电信—通信与信息系统]