改进的小波阈值消噪法应用于脉冲星弱信号处理  

Application of Improved Threshold Denoising Based on Wavelet Transform to Pulsar Signal Processing

作　　者：柯熙政[1] 汪丽[1] 倪广仁[2] 

机构地区：[1]西安理工大学自动化与信息工程学院,陕西西安710048 [2]中国科学院国家授时中心,西安临潼710600

出　　处：《西安理工大学学报》2008年第1期18-21,共4页Journal of Xi'an University of Technology

基　　金：国家自然基金资助项目(60472085)

摘　　要：利用小波变换去除噪声的基本原理和方法及消色散方法对毫秒脉冲星极弱信号进行了提取,并对噪声进行了最佳阈值选取实验研究,实现了脉冲星弱信号消色散积累后的检测和抑噪。并研究了阈值函数的几种改进方案,进而对PSR 0437-4715信号用不同方法去噪后的结果进行了分析比较,认为采用改进的阈值函数对脉冲星信号处理较采用传统的软、硬阈值函数处理具有优越性。研究结果表明改进的小波阈值消噪方法是一种提高信噪比、展示噪声和突变信号的优越方法。The basic theory and method of wavelet transform of denoising and achromatic dispersion method are used to carry out the eptraction of the millisecond pulsar weak signal and the selective experiment research is made on the optimal threshold values of noises whereby the detection and inhibiting noises affer the accumulation of pulsar weak signal achromatic dispersion can be realized. Also,several nuprovement schemes of the threshold functions are studied and the outcomes of de-noises of PSR0437-4715 signals by means of different method are analysed and compared. It is beld that the treatment of the pulsar signals by means of the improved threshold function is superior to that by using the fraditional soft and hard threshold functions. The research resuits indicate that the improved wavelet threshold denoising method is a kind of fine method to improve the ratio of signal and noise and to display noise and mutation signals.

关 键 词：毫秒脉冲星 小波变换 软阈值去噪 硬阈值去噪 阈值函数 

分 类 号：TN911.7[电子电信—通信与信息系统]