Moving Ship Velocity Estimation Using TanDEM-X Data Based on Sub-Aperture Decomposition

Abstract

In this letter, a velocity estimation method for moving ships in SAR images is proposed based on a sub-aperture decomposition technique. In contrast to traditional methods, our method needs only a few SAR imaging parameters besides the SAR image itself. The behavior of moving ships in sub-aperture images is theoretically analyzed and the ship motion parameters in azimuth direction are accurately estimated. The proposed approach was tested on real SAR stripmap images acquired by TanDEM-X, a twin satellite SAR constellation. The estimated azimuth velocities perfectly fit the data recorded by the international Automatic Identification System (AIS).