On robust beamforming for InSAR phase estimation

In InSAR signal processing, the performance of the interferometric phase estimation degrades in the case of image coregistration errors and spatial steering vector errors. In this letter, a method of interferometric phase estimation based on robust beamforming is introduced. The proposed method can take advantage of the optimal weighted joint data (OWJD) vector and of the robust adaptive beamformer to auto-coregister the SAR images and mitigate the effect of the spatial steering error on the interferometric phase estimation. Theoretical analysis and experimental results show that the method can provide accurate estimation of the interferometric phase in the presence of the coregistration error and spatial steering vector error. Numerical results on the simulated and real data demonstrate the effectiveness and robustness of the proposed method. (C) 2010 Elsevier GmbH. All rights reserved.