On-orbit signal processing procedure for determining Microwave Radiometer non-linearity

This paper presents a novel signal processing approach used to diagnose non-linear (gain compression) operation of the MicroWave Radiometer (MWR) flown on the Aquarius/SAC-D satellite. This instrument was commissioned in September 2011, and on-orbit observations of blackbody earth emissions (brightness temperatures) have been evaluated over the past year. Results are presented, which suggest that the radiometer system is slightly non-linear, and the resulting receiver gain is a function of the observed radiometric brightness temperature.