Weather System Follow-on – Microwave (WSF-M) Microwave Imager (MWI) On-Orbit Performance Assessment

The Weather System Follow-on – Microwave (WSF-M) is a Department of Defense (DoD) next- generation, operational, low earth orbit, environmental satellite system that provides space-based terrestrial environmental sensing capabilities. The WSF-M was successfully launched on 11 April,2024 to a polar sun-synchronous orbit at a nominal altitude of 833 km with Local Time Ascending Node (LTAN) of 1800 hours. The WSF-M primary payload, Microwave Imager (MWI), is a conically scanning microwave radiometer, operating at 10.85, 18.85, 23.8, 37 and 89 GHz. It has a total of 17 channels with fully polarimetric digital channels at 10.85, 18.85 and 36.75 GHz and analog channels at 23.8, 37.3 and 89 GHz, which enables to derive Ocean Surface Vector Winds (OSVW), Tropical Cyclone Intensity (TCI), snow depth, sea ice characterization, soil moisture and other environmental data products.

WSF-M Program Office led an intensive Calibration and Validation (Cal/Val) activity to ensure that the mission meets its required performance. This paper will present results from the analysis done at Aerospace towards assessing instrument sensitivity, scan bias, geolocation, polarimetric performance. Results from calibration maneuvers, radiative transfer model comparison and brightness temperature comparison with other sensors will be discussed.