基于小波变换的码元速率估计优化算法  

Symbol Rate Estimation Based on Wavelet Transform

作　　者：谭晓衡 张雪静[2] TAN Xiao-Heng;ZHANG Xue-Jing(Chongqing Key Laboratory of Bio-perception&Intelligent Information Processing,Chongqing 400044;School of Microelectronics and Communication Engineering,Chongqing University,Chongqing 400044)

机构地区：[1]生物感知与智能信息处理重庆市重点实验室,重庆400044 [2]重庆大学微电子与通信工程学院,重庆400044

出　　处：《自动化学报》2020年第8期1748-1752,共5页Acta Automatica Sinica

基　　金：国家自然科学基金(61571069);中央高校基本科研业务费(106112017CDJQJ168817)资助。

摘　　要：针对低信噪比下MPSK(M-ary phase shift keying)信号的码元速率估计问题,提出一种优化算法.该算法无需先验知识,通过Hilbert变换提取瞬时相位基带序列,经多尺度小波变换,对每个尺度下的小波系数的模值的平方进行叠加,对叠加后的结果再进行功率谱计算,在码元速率整数倍处有离散谱线,估计正确率在信噪比大于1 dB时大于90%.To solve the problem of symbol rate estimation for MPSK signals at low signal-to-noise ratio(SNR),an optimiza-tion algorithm is proposed.Without any prior knowledge,this method extracts the baseband sequence of instantaneous phase by Hilbert transform.Then,multi-scale wavelet transform is applied to the above results.The square of the modulus of the wavelet coefficients at each scale is superposed.Finally,the power spectrum of the superposition result is calculated.Theo-retical analysis shows that discrete spectral lines appear at the position of integer-times symbol rate.The results show that the correct rate of MPSK signal's symbol rate estimation is larger than 90% at SNR>1 dB.

关 键 词：MPSK信号 码元速率估计 HILBERT变换 小波变换 

分 类 号：TN911.23[电子电信—通信与信息系统]