Path-following Phase Unwrapping Algorithm based on Priority-guided Map

Phase unwrapping is a key step in interferometric signal processing. The unwrapped result directly affects the accuracy of the final reconstructed DEM. In order to improve the performance of phase unwrapping algorithm, a path-following phase unwrapping method guided by priority-guided map is proposed. Firstly, phase quality map is calculated according to the local phase characteristic, and high and low quality areas are segmented according to the quality value. Then, according to the distance between the high-quality point and the low-quality area, the guidance order of the high-quality area is determined to guide the unwrapping path to grow along the most reliable path, and the modified phase quality map is called priority-guided map. Finally, the priority-guided map is used as an indicator of the unwrapping path, and priority queue is used for quantitative guidance to obtain the final unwrapped result. In order to verify the performance of the proposed algorithm, phase unwrapping experiments are performed on simulated data and real InSAR interferogram, and the reliability of the proposed method is verified.