基于近似熵的Multi-h CPM信号调制方式识别  

Modulation Recognition of Multi-h CPM Signal based on Approximate Entropy

作　　者：刘源[1] 王世练[1] 张炜[1] 付永明[1] 陆路希 

机构地区：[1]国防科学技术大学电子科学与工程学院,湖南长沙410073 [2]盲信号处理重点试验室,四川成都610041

出　　处：《通信对抗》2015年第2期14-17,26,共5页Communication Countermeasures

摘　　要：多调制指数连续相位调制(Multi-h CPM)信号是一类包络恒定、频带利用率高的非线性数字调制信号,在军用、民用通信领域均得到广泛应用,研究其自动调制方式识别(AMR)问题具有十分重要的意义。着重对基于近似熵技术的Multi-h CPM信号调制方式识别流程进行改进。对接收信号的预处理能够减弱系统对噪声的敏感性,提高系统在较低信噪比时的识别性能;采用"分段c值"的二维特征熵计算使系统综合不同c值在不同信噪比区间体现的性能优势,在整个信噪比区间体现出较使用单一c值更好的识别性能。考虑系统噪声和多调制指数同时变化对系统的影响,利用改进的识别流程对选定的多调制指数CPM信号集进行仿真验证,系统识别率在整个信噪比区间得到明显改善。Multi-h continuous phase modulation （Multi-h CPM） is a kind of nonlinear digital modulation signals with constant envelop and efficient use of bandwidth. It has broad application both in civilian and mil- itary communication field. It is quite significant to research the problem of its automatic modulation recogni- tion （AMR）. This paper prove the feasibility of modulation recognition ofMulti-h CPM by approximate en- tropy （ApEn） technology at first, and focuses on the improvement of the original classification procedure based on the that technology. The preprocessing of the received signal can weaken the sensibility of the system to the noise, and improve the performance when the system is in low SNR region; the calculation of two-dimension feather of ApEn using ＂segmented-c＂ synthesize the advantage of different c value in different SNR region. Considering the influence of the system noise and the combined variation of the multiple modulation parame- ters, the computer simulation shows that, the modified procedure makes better performance of classification system in the whole SNR region.

关 键 词：多调制指数连续相位调制信号 近似熵 调制方式识别 预处理 分段c值 

分 类 号：TN911.3[电子电信—通信与信息系统]