Low-noise detector with RFI mitigation capability for the Aquarius L-band scatterometer

The upcoming Aquarius sea-surface salinity mission has tight requirements on backscatter measurement accuracy and stability at L-band frequencies (1.26 GHz). These requirements have driven the development of new capabilities in the scatterometer´s backend detector electronics, which are the focus of this paper. Topics include the development of flight-grade hardware aboard the scatterometer for radio frequency interference (RFI) detection and mitigation, and analog/digital electronics design techniques used to reduce system noise and achieve highly linear power detection over a wide dynamic range. We also summarize the approach taken to test the scatterometer´s processing and control functions at the level of the integrated Aquarius flight instrument, and present some recent results from the integrated testing campaign.