Post-EPS Competing Scatterometer Designs: ASCAT versus RFSCAT

Post–EPS is the successor of the EUMETSAT Polar System (EPS) and will provide continuity of operation for a range of polar orbiting Earth observation missions, among which the determination of ocean winds with scatterometry (SCA) ranks high in priority. Scatterometry presently enjoys a strong heritage: the ASCAT instrument onboard MetOp continues the series of European C-band fixed fan-beam scatterometers that started with the ERS-1 and ERS-2 satellites, whereas the American SeaWinds instrument operates in Ku-band with a rotating pencil-beam antenna. A preliminary study defining and analysing the novel rotating fan-beam RFSCAT concept was put forward in 2000. For Post–EPS a trade-off between these scatterometer concepts has been carried out. This paper focuses on an objective performance comparison between RFSCAT configurations with different rotational speeds and the ASCAT baseline configuration.