前兆水位数据处理中的小波基及其参数选择方法研究

在分析不同小波基函数特征的基础上,详细阐述了前兆水位数据处理中小波基及其参数的选择问题,针对多个水位测项进行了实例分析和比较.得到如下结论:① 在检测前兆水位数据的突变点或不规则的突变部分,选择db6、bior2.6、rbio2.6、sym4和sym6小波基效果较好,其中选用双正交小波bior2.6效果最佳;② 在小波变换分解层数的选取方面:第1～2层多适用于突变异常信号的获得,第5～6层多适用于缓变异常信号的提取;对于数据跳变异常显著的时间段,第4～6层能较好地还原被高频信息掩盖的趋势变化过程.

Selection Method of Wavelet Basis and its Parameters in Precursory Water Level Data Processing

On the basis of expounding the characteristics of different wavelet basis functions,this paper analyses the selection problem of wavelet basis and its parameters for precursory water level data processing and cases for several water level observation items are compared.It is concluded that the db6,bior2.6,rbio2.6,sym4 and sym6 wavelet basis are applicable to detect abrupt changes of precursory water level data,with the double orthogonal wavelet basis bior2.6 having the best result.On the selection of wavele...