A Microwave Four-Channel Null L-band Radiometer

摘要

The design principle of multichannel radiometric systems based on the null measurement method is described. A four-channel (with four receivers) microwave radiometer of the decimeter wave band, which uses combined pulse-amplitude and pulse-width modulations, is described. The procedure of its internal calibration using two standards is considered. The radiometer is characterized by a twofold higher fluctuation sensitivity relative to the single-channel circuit and by a better reliability.