Interferometric SAR Baseline Estimation by Partitioned High Coherence Areas

In this article, a novel interferometric synthetic aperture radar (InSAR) baseline estimation method based on ground control points (GCPs) and partitioning is proposed. Instead of introducing the existing low-resolution digital elevation model (DEM) to correct the phase jumps between high and low coherence regions in the process of phase unwrapping, we use the high coherence regional block to calibrate the interferometric parameters. In the process of calibration, the GCPs can reference for low resolution DEM, also can be obtained through the filed measurement. Because the interferometric parameters calibration does not change the absolute phase, which avoids the local DEM restriction by low resolution DEM. In addition, the block based on the coherence map avoids DEM inversion error due to overall absolute phase deviation. Gaofen-3 InSAR data of Ningbo area are used to verify the effectiveness of the proposed method.