地震信号去噪的小波方法研究

De-noising of Seismic Signals Using Wavelet Transform

简要介绍了小波去噪的基本理论和基本方法 ,说明了模极大值法和阈值法的具体原理 ,具体包括函数的奇异性及其检测方法 ,去噪模型的建立 ,并采用模极大值法和阈值法两种方法对仿真地震信号进行了计算机仿真去噪计算 .仿真结果表明模极大值法和阈值法都能有较理想的结果 ,且不需要信号的先验信息 ,都能在获得较高的信噪比增益的同时还保持了较高的时间分辨率 ;这两种方法的不足之处在于对奇异性差别不大的信号与噪声进行处理时 。

The rationale of wavelet transform de_noising and the basic theory of modulus maximum de_noising method and threshold de_noising method are introduced. Singularity of functions and its detection and the foundation of de_noising models are discussed in detail. Computer simulations adopted these two methods are also presented, which show that they both have high gain of signal_to_noise ratio and high time resolution. In comparison with Wiener filter, the results of simulation show that the new de_noise methods have good performance and needn't any priori knowledge of the signals.