Interferometry with TOPS: coregistration and azimuth shifts

Abstract:
Recently concerns have emerged regarding interferometry with TOPS, since it has been stated that a highly accurate azimuth alignment is needed to avoid phase bias in the interferometric phase. However, one should distinguish between effects due to limited geometric accuracy related to the static scene (e.g., orbit or DEM), and geophysical signals (actual azimuth displacements), which might give rise to legitimate phase jumps at the border between subsequent bursts. This paper addresses this topic and suggests an alternative methodology to process and interpret TOPS interferograms of non-stationary scenarios.