Maximum Likelihood Phase Estimation Method Based on Split-Spectrum for Multi-Frequency InSAR System

Abstract

Multi - frequency interferometric synthetic aperture radar (InSAR) has drawn more attention in reconstructing height profile. In this paper, a novel unwrapped phase estimation method based on split-spectrum strategy and maximum likelihood (ML) criterion is proposed for multi-frequency InSAR. Firstly, multiple range subband interferograms are generated with the split-spectrum strategy to form a multifrequency configuration. Then, unwrapped phase of the reference frequency is estimated via ML method modeled by the proposed normalized probability density function (pdf) which is able to remove the phase ambiguity. Finally, simulation experiments are carried out to evaluate algorithm performance. Smaller unwrapped phase error standard deviation verifies the effectiveness and exactness of the proposed method.