Improvement of Pol SAR Calibration based on the Ainsworth Algorithm

Abstract:
Fully polarimetric synthetic aperture radar (SAR) data analysis has found wide application for terrain classification, land-use, soil moisture, and ground cover classification. Critical to all analyses and applications is accurate calibration of the relative amplitudes of and phases between the various polarimetric channels. In this paper, we propose an improved algorithm to estimate the parameters stable and accurately based on the Ainsworth and the Quegan algorithms. The processing of this new algorithm is: 1) Initial the crosstalk parameters with the estimations of the Quegan algorithm; 2) Calculate the correction values of these four estimations and update the crosstalk parameters with Newton iteration method. Since there is none approximate in the process of the parameters estimation, this algorithm can accurately solve all parameters, even if the crosstalk is high. To verify the effect of proposed calibration algorithm, this paper analyse the accuracy of proposed algorithm with simulated distort PolSAR data. Then the simulated and Chinese airborne X-band PolSAR data before and after calibrated are decomposed respectively with Cloude’s algorithm. The results confirm the proposed algorithm can solve all parameters more stable and accurately.