InSAR Phase Unwrapping Algorithms with the Aid of GPS Control Points

The precision of interferometric synthetic aperture radar (InSAR) phase unwrapping can be improved by aid of global positioning system (GPS). In this paper, a new branch-cut phase unwrapping algorithm using several GPS control points as unwrapping initial points is proposed. However this algorithm cannot produce correct estimates in residues and isolated regions introduced by the placement of branch cuts. It cannot guarantee the integer properties of the unknown circle number.To solve these problems A new synthesis algorithm that combines the new algorithm with phase unwrapping algorithm with aid of GPS based on Markov random filed (MRF) is proposed. The experimental results show that the synthesis algorithm combines the advantages of new several unwrapping initial points branch-cut algorithms and algorithms based on MRF and can offer higher precision with greater spatial coverage.