Polarimetric Goldstein Filter for Interferometric Phase Denoising

Yuta Otsuka, Ryo Natsuaki, Akira Hirose

Abstract: The Goldstein filter is one of the most commonly used methods to reduce noise in interferometric synthetic aperture radar data. However, the low filtering performance in highly noisy areas remains unsolved. In this paper, we propose an adaptive filter in the biquaternion Fourier domain (BQFD filter) to improve the filtering performance even in highly noisy regions. This method represents PolInSAR data in a biquaternion form to process the interferometric fringes of different polarimetric channels as a single signal. By using the biquaternion Fourier transform, the fringes can be effectively separated from the noise because of the high correlation of the fringes and the low correlation of the noise between the polarimetric channels. Experimental results show that digital elevation models generated with the BQFD filter are more accurate than those generated with the Goldstein filter.