The calibration target for FY-3 space-borne microwave humidity sounder

A general introduction is presented in this digest to describe configuration, operational theory and technical specifications of the calibration target for FY-3 space-borne microwave humidity sounder of china. The target with the temperature-adjusted function based on PID controller can provide the brightness temperature output form 90K~350K and its uncertainty is 1.2K~1.6K (k=2) in 75GHz~220GHz. The traceability for brightness temperature of the calibration target is achieved by calibrating sensors embedded inside the calibration target and by emissivity international comparison. The experimental results and further analysis are also provided in this digest.