A Locally Adaptive Filter for Noise Filtering of InSAR Interferogram

An adaptive filtering approach for interferograms is proposed,which is a modification to the Lee adaptive complex filter.Firstly,the approximate maximum-likelihood(AML) method is introduced.Based on local frequency estimation,the sizes and rotation angle of the filtering window are calculated.The pixels in the filtering window are obtained by an interpolation to make the pixels in the filtering window have more approximately homogeneous values.Secondly,the results are obtained by Lee filtering method.Experimental results show that the proposed method can filter the phase noise effectively,and preserve the details of interferometric fringes better.