A method for calibrating the ground-based triple-channel microwave radiometer

Based on the high correlation between the brightness temperatures (TBs) measured by the ground-based triple-channel microwave radiometer at 20.6, 31.65, and 90.0 GHz, a new calibration method is proposed with which the calibration coefficients and sky TBs can simultaneously be obtained by solving the systems of nonlinear equations expressing the radiometric outputs at 6 observation angles. The feasibility of this calibration method has been demonstrated by numerical simulations. Its further test will be carried out in applications with realistic measurement data.