A new adaptive high resolution wide area SAR with multi-feed reflector antenna

RST Radar Systemtechnik AG is involved in design of new Satellite SAR Systems for several decades now. RST´s specialty is the design of Satellite SAR with very high performance-to-cost ratio. The newest activity was directed towards a Reflector Antenna based SAR satellite allowing a wide area viewing combined with very high resolution. The RF-output power situation can be solved by parallelization of TWTAs on one hand side through a Buttler Matrix and on the other hand by operating parallel feeds in elevation, where the output power combination is performed at the Reflector. The latter easily solves the Multipaction Problem, because the high RF-fields are not routed through a waveguide, couplers and circulators being Multipaction sensitive. Finally, the Link-Budget can be improved by a SCORE (Scan On Receive) operation operating the SAR with several feed horns in elevation switching between them synchronized with the incoming Radar echoes. The paper will provide an overview on the next generation of high-RF-bandwidth SAR combined with wide swath and adaptive switching between elevation angles. It gives an in-sight into present planning of next generation of SAR Satellites under the umbrella of Design-to-Cost.