结合等值线滤波条纹边缘保持能力强和Goldstein滤波平滑效果好的特点，并且引入伪相干值对Goldstein滤波因子进行改进，提出InSAR干涉图的等值线中值–Goldstein二级滤波方法。模拟数据和真实数据的实验结果证明，强噪声干涉图经过新方法滤波后噪声水平大大降低而且分布均匀，条纹细节信息保持良好，在原本看不到信号的区域也可以恢复部分条纹，并适用于条纹密集和曲率变化大的干涉图。

At present, most of the traditional fi lters such as Goldstein, Lee, Median, Mean, and Periodic fi lter, can not meet the demand of noise suppression for interferograms contaminated by phase noise. Repeat fi ltering, however, will result in serious loss of fringe pattern. In this paper, a two-step fi lter is presented. The fi lter inherits the good edge preservation characteristics of the Contoured window fi lter and the strong smoothing capability of the Goldstein fi lter. In addition, it introduces the pseudocoherence of interferogram to improve the adaptiveness of the Goldstein fi lter. Experimental results with both simulated and real data show that the proposed fi lter performs quite well both in noise reduction and in detail preservation. Moreover, it can partially recover continuous interferometric fringes from area without signals, and is applicable for interferograms with very dense and heavily curved fringes.