Interferometric SAR Phase Filtering With SURE-Based Non-Local Method

As the phase of the interferometric synthetic aperture radar (InSAR) contains abundant information for many earth observation activities, the interferometric phase denoising is an important step before InSAR processing and application because of its significant influence on the following steps. And this paper focused on the interferometric phase filtering and proposed a new filter based on the Stein's unbiased risk estimate (SURE)-based nonlocal means method. The SURE formula is more convenient for estimating the mean square error (MSE) from the noisy image only. Due to advantages of both the nonlocal means and the Stein's unbiased risk estimate, the proposed filter is exploited to the interferometric phase in the complex domain in the paper. Except for the denoising performance, the proposed method is more focused on preserving more useful information in the InSAR phase fringe patterns, such as the phase jumps utilized for urban information retrieval. The experiments on both the simulated data sets and the real data sets were implemented and analyzed to demonstrate the effectiveness of the proposed filtering method.