Techniques for achieving wide swath coverage with spaceborne SAR systems

Designs for increasing SAR coverage beyond 200 km are discussed using figures for ERS-1 as baseline. The technological demands of each concept are assessed. Although for the extended antenna system the critical area is antenna technology, processing also needs to include multiple range looks. Squinted SAR systems require significantly more complex processing, increased pulse bandwidth, and slightly longer antennas. These two systems provide continuous coverage of a wide swath unlike the others which only cover discrete swaths. The multiple receive beam technique requires little new technology except for signal reception where two (or more) antennas or complex multiple beam formation is required. The dual pulse system requires large amounts of power which could prove difficult to produce. The multiple SAR systems require isolation of separate systems and storage and deployment of two antennas.