Real-time monitoring microwave dicke radiometer based on reference load temperature

Abstract

The invention discloses a real-time monitoring microwave dicke radiometer based on a reference load temperature and belongs to the field of microwave passive remote sensing. The radiometer comprises a dicke input switch, wherein a first end of the dicke input switch is sequentially connected with a radio frequency and intermediate frequency amplifying circuit, a square law detector, a low frequency amplifier, a synchronous detector, a low pass filter and a data collecting and processing module, a second end of the dicke input switch is switched between a reference load and an antenna under the driving of a switch signal generator, and a temperature measuring circuit is arranged on the reference load and connected with the data collecting and processing module. The reference load of the microwave dicke radiometer is not required to be kept in a constant temperature state, only the temperature measuring circuit is used for monitoring the temperature changes of the reference load in real time, the monitored variable quantity of the temperature of the reference load is plugged into a radiometer scaling equation for modification, and an antenna temperature of the measured scene is obtained. According to the real-time monitoring microwave dicke radiometer based on the reference load temperature, the measuring accuracy is improved and the structure of the existing microwave dicke radiometers is simplified.

Description

technical field [0001] The invention belongs to the technical field of microwave remote sensing and precision measurement, in particular to a microwave Dicke radiometer based on real-time monitoring of reference load temperature. Background technique [0002] Microwave radiometer is the core equipment of passive microwave remote sensing, and it is a tool for detecting, imaging and judging the microwave radiation characteristics of ground objects and targets. All objects above absolute zero radiate electromagnetic wave signals. In the microwave frequency band, the microwave signals radiated by objects themselves are incoherent and extremely weak signals. Therefore, unlike traditional receivers that receive coherent signals and whose signal-to-noise ratio is always greater than 1, microwave What the radiometer receives is the noise power radiated by various objects that is much smaller than the noise power of the machine. It is essentially a high-sensitivity receiver in the mi...

AI Technical Summary

Problems solved by technology

At present, under long-term and harsh working conditions, it is very difficult to make the temperature change of the reference load less than 0.1 degrees through constant temperature technology, which limits the measurement accuracy of the microwave Dicke radiometer

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