A filtering algorithm for InSAR interferogram based on wavelet transform and median filter

The interferogram of InSAR is often corrupted by noise. Therefore, the filter of the interferogram is necessary in InSAR processing. In order to overcome the drawbacks of conventional filters leading to a degradation of spatial resolution and edge blur, a novel filtering algorithm based on wavelet transform and median filter is proposed for InSAR interferogram in this paper. The key point of the proposed algorithm is the introduction of the adaptive center weighted median filter into the wavelet transform to filter out the noisy coefficients, which can suppress the noise adaptively. The results with real data obtained from SIR-C/X-SAR are presented to verify the effectiveness of the proposed method.