Digital Beam Forming Techniques for Spaceborne Reflector SAR Systems

Abstract:
A new generation of space borne radar remote sensing systems is currently being under investigation. The concept of reflector antennas in conjunction with feed arrays, which is well established on communication satellites, is exploited for Synthetic Aperture Radar (SAR) sensors. One of the main goals for future SAR systems is to replace parts of the analog radio frequency hardware, being a major cost driver, in the receive chain with digital components. These innovative systems allow a flexible data handling and the implementation of digital beam forming (DBF) concepts. The main advantage of multi channel systems is to overcome the inherent limitations of state-of-the-art SAR instruments and enable the production of wide swath high resolution imagery at the same time. In the frame of these developments DBF algorithms, aiming at a performance improvement, are analyzed and adapted to the requirements of reflector based SAR sensors. The DBF concepts presented in this paper are illustrated by means of numerical simulations.