The Sentinel-1 SAR electronics performance

The Sentinel-1 C-band Synthetic Aperture Radar (SAR) instrument is currently under testing by EADS Astrium. The SAR Electronics Subsystem (SES) which provides the core functionality, control and monitoring of the SAR Instrument has completed its verification and qualification at EADS Portsmouth. The SES generates and transmits RF Chirp pulses centred at 5405MHz with up to 100MHz bandwidth. In receive the echo signal is down converted and digitized at an IF close to baseband. Then, the digital data is processed using efficient filtering and data compression algorithms and is output via high-speed serial data links. The Sentinel-1 SES represents a new generation of central electronics following on from previous SAR missions ERS-1/2, ASAR and Radarsat-2. New technologies have been embraced and developed to produce a smaller lighter single box solution. The design takes benefit of progress in FPGA and ASIC technology to cope with the high load of the complex digital data processing. Verification of the SES performance in terms of phase, amplitude and IRF performance, signal isolation in Tx and Rx chains, Noise Figure and spurious signals rejection has confirmed compliance to the demanding requirements. This paper reports the results of this successful test campaign and discusses the good performance achieved.