An Efficient Minimum-Discontinuity Phase-Unwrapping Method

Abstract

Phase unwrapping (PU) is significant in reconstructing the digital elevation model of a scene from its interferometric synthetic aperture radar (InSAR) data. The classical minimum discontinuity (MD) PU algorithm by Flynn is highly accurate but involves time-consuming computation. To overcome this shortcoming, we proposed a preunwrapping-assisted MD (PAMD) PU method, which has high efficiency and the same unwrapping quality as Flynn's algorithm. In the PAMD method, the phase image is first unwrapped by the preunwrapping algorithm, which generates and optimizes the dipole cuts. The preunwrapping algorithm is fairly fast, and the obtained result is much closer to the optimal solution of MD; therefore, it can be further optimized by Flynn's algorithm efficiently. Tests on simulated and real InSAR data confirm the accuracy and the efficiency of the proposed method.