A New Differential Calibration Method for Measurement Accuracy Improvement of Atmospheric Radiation

A new differential calibration method approach has been proposed for atmospheric radiometer for achieving better stability and sensitivity in this paper. Conventional total power radiometer has been modified to enhance the sensitivity, whereas inherent architecture of the system assures better stability than Dicke radiometer. First, the approach has been evaluated at V-band frequency for temperature profiling followed by at K-band frequency for humidity profiling. Design and simulation of the proposed method have been presented here. The proposed calibration method involves alternately switching two separate noise sources with different Excess Noise Ratio (ENR) values with precision timing. Simulation has been carried out to validate the calibration method. Measurement accuracy of atmospheric radiation during gain variation of the system has been minimized.