基于小波变换的通信信号码元速率估计

自动调制识别在电子侦察和电子战领域中扮演突出角色。怎样在没有先验知识的情况下对码元速率进行估计是调制识别领域一个重要的问题。小波变换可以有效地提取数字通信信号的瞬时突变特征。本文提出了一种估计码元速率的方法,这种方法在无先验知识的情况下对MPSK信号的码元速率进行估计。在matlab仿真中,如果我们选取合适的小波函数,小波变换幅度在相位突变时就会出现峰值,而且峰值之间的间隔是码元周期的整数倍。计算机仿真结果证明了该方法在低载噪比(CNR)下的有效性。

Symbol Rate Estimation of Digital Signals Based on Wavelet Transform

Automatic modulation identification of communication signals plays an important role in electronic surveillance and electronic warfare systems. How to estimate symbol rate of digital signals without any apriori knowledge is a significant problem in the field of modulation identification.The wavelet transform (WT) can effectively extract the transient characteristics in a digital communication signal. A method was discussed to estimate symbol rate of MPSK signals using wavelet transform without any apriori knowledge.In matlab simulation,if a proper wavelet function is chosen,the WT magnitude of digital communication signals will peak at the time where phase changes occur. Consequently the separation of the peaks is an integral multiple of the symbol period. In addition,computer simulation results show the good performance of the method even at low Carrier to Noise Ratio (CNR).