A dual-domain interferometric phase filter

Abstract

This article presents a dual-domain phase filter for synthetic aperture radar (SAR) interferometric phase images. The dual-domain phase filter consists of a refined Baran and an adaptive mean filter. The interferometric phase is transformed into the complex domain and filtered by the refined Baran filter, in which the absolute value of the complex phase spectrum is adjusted using a threshold and the structural similarity coefficient. Then, the complex residual phase is filtered by the adaptive mean filter and added back to the previously filtered complex phase to generate the final output. Taking advantage of both filters, the dual-domain phase filter can not only avoid creating false information in very low coherence areas, but also effectively suppress noise in other areas. By using one real SAR data set, the performance of the dual-domain phase filter, in terms of noise reduction and computational efficiency, is reported and compared with other existing filters.