Advanced Microwave Scanning Radiometer 3 (AMSR3)

Advanced Microwave Scanning Radiometer 3 (AMSR3) is an operational conical-scanning passive microwave radiometer on GOSAT-GW for water-cycle observations.^[1][2] Its observing set comprises 6.925, 7.3, 10.25, 10.65, 18.7, 23.8, 36.42, 89, 165.5, and 183.31 GHz, with horizontal and vertical polarization modes and a 40 rpm conical scan.^[3][1]

The 10.25 GHz low-frequency channel is a documented addition to the AMSR heritage, while JAXA frames 165.5 GHz, 183.3 +/- 7 GHz, and 183.3 +/- 3 GHz as newly added high-frequency channels; detailed channel tables also distinguish 89 GHz A/B rows plus both 183.31 GHz offset channels.^[1][3] Operational coverage is about 1500 km swath with 99.9 percent of Earth within 3 days, and detailed instrument records also carry a 1535 km swath value.^[1][3] JAXA reported initial AMSR3 observation data during functional verification in August 2025, and passive microwave radiometry is demonstrated on GOSAT-GW.^[2] AMSR3 combines all-weather microwave brightness-temperature continuity, dual-polarization channels, and high-frequency humidity and precipitation sensitivity in one sensor package.^[1][3]