Bistatic SAR Imaging with Sentinel-1 Operating in TOPSAR Mode

Abstract

In this paper, we propose a bistatic synthetic aperture radar (SAR) imaging procedure using a Sentinel-1 satellite as transmitter of opportunity and a stationary ground receiver. The procedure is designed for the standard operating mode of Sentinel-1 satellites - Terrain Observation with Progressive Scans SAR (TOPSAR) and essentially comprises the synchronization between satellite transmitter and ground receiver and the bistatic focusing algorithm. The proposed imaging method takes into account the particularities imposed by the antenna beam sweep from back to forth (specific for TOPSAR mode) and exploits the position vectors and transmission timestamps annotated in the ancillary data from the monostatic raw image. The methodology is demonstrated with a bistatic acquisition performed with Sentinel-1A over an area of Bucharest city, Romania.