基于循环谱相关方法的MFSK信号识别

Research on Identification of MFSK Signals Based on Cyclic Spectral Correlation Function

由于通信信号调制样式复杂多样,如何有效地识别通信信号调制类型是一个十分重要的课题。传统的信号处理都是假设所要处理的信号为随机平稳信号,但是在实际应用中,通信信号具有循环平稳性,是一种特殊的非平稳信号。首先介绍了循环平稳信号的特性循环谱相关概念,推导出MFSK信号的循环谱相关函数,分析了MFSK信号特征谱规律和可用于类内识别的特征参数,设计出MFSK信号的类内识别算法,仿真实验表明该算法能有效区分MFSK信号,并且在低信噪比下识别效果良好。

Because of the complexity of communication signal modulation, the recognition of communication signal modulation type becomes particularly important.The signal is assumed to be stationary in the conventional signal-processing field, but the communication signal is a special non-stationary signal which has cyclostationary feature in the practical application. This paper deduces the spectral correlation of the MFSK signals, analyzes the law of the MFSK signal＇s characteristic spectrum and the characteristic parameter for the intra-class identification, works out a method which can be used to identify the MFSK signals. The simulation results show the effectiveness of this method in identifying the MFSK signals even when the signals are buried by noise.