基于频谱和瞬时自相关的雷达信号调制识别

Radar signal modulation recognition based on spectrum and instantaneous autocorrelation

针对雷达信号脉内调制方式的快速识别问题,提出了一种基于瞬时自相关的幅度和相位特征的识别方法。根据带宽将信号粗分为调相信号和调频信号,通过时域累加进行平滑处理以增强信号的幅度跳变特征、通过增大时延对相位进行解相位模糊并对采样区间取均值的方法增强低信噪比下调频信号的特征。实验结果表明:在信噪比高于5 dB时能100%识别出6种调制信号,有效提高了算法抗噪性能,并具有计算复杂度低的特点。

In order to solve the problem of fast recognition of intra-pulse modulation of radar signal,a recognition method based on instantaneous autocorrelation was proposed.In this method,the signals were roughly divided into phase-modulated signals and frequency-modulated signals according to the bandwidth.The amplitude jump characteristics of the signal were enhanced by smoothing in time domain,and the characteristics of low signal-to-noise ratio down-frequency signals were enhanced by increasing the time delay to resolve phase blurring and taking the mean value of the sampling interval.The experimental results show that six kinds of modulated signals can be identified when the signal-to-noise ratio is higher than 5dB,which effectively improves the anti-noise performance of the algorithm and has the characteristics of low computational complexity.