一种基于循环平稳性的CPM信号符号速率盲估计算法

Novel Blind Estimation Algorithm for the Symbol Rate of CPM Signals Based on Cyclostationarity

根据循环平稳有关理论,通信信号的非线性变换频谱中存在体现各阶循环平稳性的离散谱线,谱线位置对应着信号载波频率和符号速率的线性组合,提取这些谱线可以完成信号的一些基本参数估计。通过分析CPM信号瞬时频率函数的循环平稳性,利用二次方谱与符号周期的关系,提出了一种新的CPM信号符号速率盲估计算法。实验结果证实了理论分析的正确性,并且表明该算法预处理要求低,具有较好的抗噪声性能,能够实现衰落信道下CPM信号符号速率的有效估计。

According to the theory of cyclostationary,some discrete spectral lines,corresponding to the linear combination of communication signals＇ carrier frequencies and symbol rates,are present in nonlinear transform of signals to reflect cyclostationarity.Some basic parameters can be estimated by extracting the spectral lines.Based on the cyclostationarity study of instantaneous frequency function of CPM signals,the relationship between the square spectrum and symbol period is discussed and a novel blind symbol rate estimation algorithm is proposed.The experimental results sustain the theoretical analysis and indicate that the proposed algorithm with lower pre-processing requirement has good anti-noise performance.This method can also be used to accomplish effective symbol rate estimation of CPM signals in fading channels.