COMPARISON OF TWO PHASE UNWRAPPING METHODS FOR PSP TIME SERIES ANALYSIS

Abstract

Phase unwrapping is a key issue for PSP (Permanent Scatters Pairs) time series analysis. In this paper, the LLL method and grid search method are applied for determining elevation error and velocity difference in LOS for each PSP, and the RMS is used to assess the correctness of the solution. The Delaunay triangulation is used to formulate PSPs, which are used to unwrap elevations and velocities of all PSs with respect to a given reference point. The simulation examples with real SAR satellite orbits show that if the atmosphere noise is less than 2 radians and the random noise is less than 10 degrees, LLL method can obtain correct solution while grid search can obtain solution with a small error probability.