基于提升静态小波变换的风廓线雷达地杂波抑制方法

摘要

针对现有的基于离散小波变换(DWT)去风廓线雷达地杂波技术中最佳分解层数与阈值不好确定，且DWT不具有平移不变性的问题，介绍静态小波变换(sWT)的提升实现方法，提出一种基于提升SWT的风廓线雷达地杂波抑制方法。这种方法通过计算各层小波系数上的2阶原点矩来确定最佳分解层数，并以最邻近地杂波频段的2个频段的平均值作为阈值。由于采用提升实现方式，其运算量相对于传统的基于DWT去地杂波的方法并没有很大的提高，且能适用于较低杂信比的情况。仿真结果验证算法的有效性。%In the existing method based on wavelet discrete wavelet transform (DWT) to removing ground clutter from wind profiler data, it is difficult to determine the best decomposition level and the threshold, and the DWT has not the characteristics of translation invariance of the wavelet coefficients. The lifting methods of static wavelet transform (SWT) was introduced firstly. And then a method to removing ground clutter from wind profiler data based on Lifting Static Wavelet Transforms was proposed. This method determines the best decomposition level by calculating the 2-order moment of the wavelet coefficients at all levels, and select the threshold through the average of the two bands which are adjacent to the clutter band. The new methods can be applied to lower signal to clutter ratio (SCR) whose calculation amount is a little more than that of the traditional method. The simulation results show the validity of the algorithm.