MTVZA-GY Imaging/Sounding Microwave Radiometer

MTVZA-GY is a conical-scan passive microwave radiometer carried on Meteor-M N2-4, providing 29 channels across 21 frequency groups spanning 10.6 GHz to 191.06 GHz.^[1] The instrument name's GY suffix honours Russian instrument designer Gennady Ya Gus'kov (1919-2002).^[2]

Channels are arranged in groups covering the 10.6 and 18.7 GHz window frequencies, the 23.8 GHz water-vapour line, the 31.5 and 36.7 GHz window bands, oxygen absorption channels near 42, 48, 52.8, and 57 GHz, a 91.655 GHz window, and water-vapour sounding channels at 175.56, 183.31, and 191.06 GHz.^[1] Both horizontal and vertical polarisation are available on imaging channels.^[1] Conical scan geometry provides a consistent incidence angle across the 1500 km swath, with a scan period of 2.55 seconds and a scan angle of 53.3 degrees.^[1]

Ground resolution varies with frequency: the 65 cm antenna produces an instantaneous field of view of approximately 130 km at 10.6 GHz, 16 km at 91.655 GHz, and approximately 12 km at 183.31 GHz.^[2][1] The instrument covers near-global area twice daily.^[1] Applications include passive microwave surface imaging, atmospheric temperature and humidity profiling through oxygen and water-vapour absorption channels, and precipitation retrieval from window-channel brightness temperatures.^[1]

MTVZA-GY is an evolution of the MTVZA microwave radiometer previously flown on Meteor-3M-1.^[2]