Abstract:

Interference synthetic aperture radar (InSAR) acquire target’s altitude according to the difference in distance which derives from the absolute phase difference between the corresponding pixel points of two synthetic aperture radar (SAR) images. But the phase difference of interference aperture radars is limited in (-π,π］, therefore the phase unwrapping is one of the key steps in InSAR signal processing. Due to the effect of noise and under sampled region, an accurate phase unwrapping has been quite difficult, path following is a major method in phase unwrapping. In the path following, the shorter the cut length is, the better the effet of phase unwrapping is, so how to establish a branch tangent is very important. An improved genetic algorithm is presented to establish the shortest branch tangent connecting the positive and negative residual error points by means of the traveling salesman problem (TSP) approach for solving the shortest path. The experiment result shows that the proposed algorithm can effectively avoid the unwrapping process of “isolated island phenomenon” to happen.