MBInSAR-BM4D: A Multibaseline InSAR Interferometric Phase Noise Suppression Method Based on BM4D

Multibaseline interferometric synthetic aperture radar (MB-InSAR) has attracted widespread attention as it can improve the measurement accuracy of elevation or deformation by exploring baseline diversity. However, the interferometric phase is normally contaminated by phase noise, which directly affects the measurement accuracy. In this article, an MB-InSAR interferometric phase noise suppression method based on BM4D (MBInSAR-BM4D) is proposed. To increase the number of similar cuboids for grouping, a topographic phase compensation strategy is introduced, which can reduce fringe density in complex topography. In addition, to accurately select similar cuboids from residual interferometric phase stack and collect them into 4-D groups, the generalized likelihood-ratio (GLR) test is applied, in which the observed amplitude, coherence, and phase are utilized simultaneously for improving the grouping accuracy. After performing collaborative filtering and aggregation on 4-D groups, the MB-InSAR interferometric phase stack noise suppression results are obtained by adding the reference phase back to the corresponding filtered residual interferometric phase. All interferometric phases are fully exploited to facilitate MB-InSAR phase stack filtering performance enhancement. Experimental results on both the simulated and real MB-InSAR data demonstrate that the proposed MBInSAR-BM4D provides superior noise suppression and fringe detail preservation for the MB-InSAR interferometric phase stack.