Calibration of a three-band microwave radiometric system by an external noise signal source

Abstract

The article considers a method of solving the problem of calibration of a tri-band microwave radiometric system by an external source of noise signal. The peculiarity of the given method of calibration is the location of the calibrated noise signal source in the base of the common antenna mirror with reception to the common aperture of the system’s illuminator. The questions of technical realization of a noise source as a broadband noise generator taking into account frequency dependence of output noise power value supplemented by an attenuator for obtaining a two-level calibration signal are considered. In article the theoretical positions underlying the given way of calibration in values of measured radio-luminous temperature are resulted, and time dependences of measurements of radio-luminous temperature of atmosphere are shown at an antenna direction in a zenith with inclusion of an external source of a noise signal at performance of calibration of microwave radiometric system.