The study of Interferogram denoising method Based on Empirical Mode Decomposition

This paper proposes a new filter based on empirical mode decomposition that is based on different characteristics of signal with noise in different IMFS for suppressing speckle in SAR interferogram is proposed. At first empirical mode decomposition is used to divide signal and processed high-frequency IMF signals separately by adaptive filter. The denoising effect of the proposed method, usual filter and multiscale EMD filter was investigated by experiment. When the part related to the speckle is subtracted from the original interferogram, the speckle noise is reduced. The result is compared with the four other methods of mean filter, median filter and the adaptive filter, which shows that EMD filter method is powerful to interferogram speckle noise reduction, as well as it can preserve fine details in the interferogram that are directly related to the ground topography and maintain phase values distribution.