About this Journal Submit a Manuscript Table of Contents
International Journal of Antennas and Propagation
Volume 2009 (2009), Article ID 614931, 13 pages
Application Article

Performance Comparison of Reflector- and Planar-Antenna Based Digital Beam-Forming SAR

Microwaves and Radar Institute, German Aerospace Center (DLR), 82230 Wessling, Germany

Received 15 October 2008; Revised 23 January 2009; Accepted 17 March 2009

Academic Editor: Giovanni Toso

Copyright © 2009 Marwan Younis et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The trend in the conception of future spaceborne radar remote sensing is clearly toward the use of digital beamforming techniques. These systems will comprise multiple digital channels, where the analog-to-digital converter is moved closer to the antenna. This dispenses the need for analog beam steering and by this the used of transmit/receive modules for phase and amplitude control. Digital beam-forming will enable Synthetic Aperture Radar (SAR) which overcomes the coverage and resolution limitations applicable to state-of-the-art systems. On the other hand, new antenna architectures, such as reflectors, already implemented in communication satellites, are being considered for SAR applications. An open question is the benefit of combining digital beam-forming techniques with reflector antennas. The paper answers this question by comparing the system architecture and digital beam-forming requirements of a planar and a reflector antenna SAR. Further elaboration yields the resulting SAR performance of both systems. This paper considers multiple novel aspects of digital beam-forming SAR system design, which jointly flow into the presented system performance.