An Interferogram Filtering Algorithm Using Shearlet Transform

In interferogram filtering, traditional threshold filtering algorithm based on wavelet transform does not consider the statistical properties of SAR's interference phase, and the filtering effect obtained in the low coherence regions is not satisfactory.This paper presents a kind of phase noise filtering algorithm combining the shearlet transform and standard deviation of phase.The algorithm uses the phase standard deviation to correct the filter threshold and improve the filtering effect.In addition, in order to evaluate the filtering effect and to select the appropriate filtering method for the measured data, a local mean square error distribution of the simulated interferogram is proposed as the filtering quality evaluation index.Compared with Goldstein filtering, wavelet filtering, optimal direction fusion filtering and shearlet soft threshold filtering, the results show that the proposed method can not only weaken the noise of interferogram, but also keep the details and avoid the weak filtering in low coherence regions.