Inverse SAR Processing for Maritime Awareness

This paper presents a novel processing chain based on Synthetic Aperture Radar (SAR) and Inverse SAR (ISAR) techniques to refocus SAR images of moving maritime targets and estimate their motion parameters. The proposed processing chain was developed and extensively evaluated The algorithm was tested on a large dataset of COSMO-SkyMed (CSK) and Cosmo Second Generation (CGS) dataset including 300 vessels, and spanning different maritime scenarios, in order to account for many contingencies such as the sea states, the ship movements, and the mutual geometry between the SAR orbit and the course of ship. To assess the refocusing capability, quantitative contrast measurements of the refocused images were conducted. The accuracy of vessel speed estimation was evaluated by comparing the results with Automatic Identification System (AIS) data as a reference. The key contribution of this work lies in demonstrating the effectiveness of ISAR processing applied to satellite SAR images for near real-time Maritime Awareness applications. This was achieved through the development of a robust and fully automatic processing chain, as well as an extensive experimentation and validation process.