Sentinel-1 Next Generation: Enhanced C-band Data Continuity

Abstract:
This paper presents an overview of the planned Copernicus Sentinel-1 Next Generation (NG) mission, which will provide enhanced C-band data continuity through the next decade (2030s) in support of operational Copernicus services that are routinely using Sentinel-1 data. In this context, we consider novel imaging capabilities in view of addressing challenging mission requirements, and existing and evolving applications. The recently completed Phase A/B1 studies focused on the definition of novel SAR system concepts and the related analysis of key SAR performance parameters in view of achieving the envisaged performance enhancements. As part of the studies, pre-development activities for critical SAR technologies were implemented to ensure the required technology readiness. The studies concluded that the use of phased array antenna systems is the most suitable approach for the implementation of the Sentinel-1NG mission. The planar SAR antenna concept would enable the implementation of a multi-channel High Resolution Wide Swath (HRWS) SAR system using ScanSAR modes exploiting digital beamforming techniques, such as Scan On Receive (SCORE) and Multiple Azimuth Phase Center System (MAPS). In addition, the multi-azimuth channel HRWS concept would provide an Along-Track Interferometry (ATI) capability for an improved estimation of the radial velocity of ocean surface currents and ocean-going vessels. In addition, the Phase A/B1 studies comprised the analysis of potential SAR concepts regarding their performance characteristics in view of supporting the planned ESA Earth Explorer bistatic Harmony SAR mission.