小波变换在大地回波噪声处理中的应用

摘要

Based on the wavelet transform and its multiscale decompositions, it is possible to grasp the slight changes of characteristic information carried by image's edge on every scale. The laws have been analysed, which are followed by local maximal of wavelet transform modulus of white noise and continuous signal on different scales. An algorithm is developed to remove white noises from signals by analyzing the evolution of local maximals of wavelet transform modulus at acrossing scales. The numerical simulation proves that the algorithm is efficient. It is possible to provide an efficient approach to low-SNR radar signal detection in the future.%基于小波变换的多尺度分辨特性，作者对连续信号、脉冲信号和宽平稳白噪声在小波域中不同分解尺度上的模极大值变化规律进行分析，根据它们的变化规律用Mallat快速算法设计出一套用于抑制低信噪比雷达回波中的干扰噪声、最大限度提纯真实回波信号的算法.仿真实验证明，该算法对抑制噪声作用明显，能较好地提纯雷达回波信号，这为低信噪比下雷达回波信号检测提供了一条有效途径.