Using Phase Unwrapping Methods to Apply D-InSAR in Mining Areas

Phase unwrapping is one of the key processing steps of D-InSAR (Differential Interferometric Synthetic Aperture Radar), and its accuracy has a great impact on the accuracy of interferometric deformation results. Therefore, it is necessary to choose the proper phase unwrapping method for mining deformation monitoring with different coherence by the comparative study of different phase unwrapping methods, because the coherence is different for different mining areas. In this paper, 2 data sets of different coherence Sentinel-1A data in Xuangang mining areas were processed using 3 different D-InSAR unwrapping methods: Region Growing, Minimum Cost Flow, and Delaunay MCF by SARscape software. Through statistical analysis of phase unwrapping results and comparative analysis of the difference between the theoretical deformation value and the deformation value calculated by SARscape, the Delaunay MCF unwrapping method is found to be the best to monitor low-coherence mining areas under most conditions. However, the Minimum Cost Flow method is a better choice when the coherence of mining areas is high, and smoother and more continuous phase unwrapping results can be obtained by selecting a mining area with better coherence.