A comparison of different techniques for atmospheric artefact compensation in GBSAR differential acquisitions

Abstract

In this paper, a comparison of different techniques for compensating the atmospheric artifacts in Ground-Based SAR zero-baseline acquisitions at X-Band is presented. The way the fluctuation of atmospheric parameters like temperature, pressure and humidity among successive scans affects interferometric phases is pointed out and a simple model based on the refractivity index variations is given to explain such a behavior. Three alternative methods for the artifact removal, respectively based on the differential phase 1D unwrapping, 2D unwrapping and the Chirp-Z transformation are described and quantitatively compared using a reference dataset. The advantages and the limitations of each technique are finally drawn.