Digital automatic compensation microwave radiometer

Abstract

The invention provides a digital automatic compensation microwave radiometer which comprises an antenna, a microwave switch, a total power microwave radiometer receiver, a digital automatic compensation system, a high-precision platinum resistor temperature detecting circuit, a temperature detecting platinum resistor of a microwave front-end component, a matching load and a temperature-detecting platinum resistor of the matching load, and a physical temperature detecting platinum resistor of the antenna, wherein a high-precision platinum resistor temperature detecting sensor is used for measuring the physical temperatures of the microwave front-end component, the microwave antenna and the microwave matching load in real time; and a computer is used for realizing two operation processes of system gain compensation and noise temperature compensation. By the digital automatic compensation microwave radiometer, the influence of gain fluctuation on the measuring precision and the influence of the uncertainty of the noise caused by the system noise temperature TREC, antenna and feeder loss L Eta on the measuring precision are eliminated, and an accurate luminance temperature value which directly reflects that the antenna of microwave radiometer receives a target noise signal TA can be provided. The microwave radiometer has the advantages of small volume, light weight and low power consumption, is capable of shortening the waiting time for starting up and is greatly convenient for user to use outdoors and transport.

Description

technical field [0001] The invention belongs to the technical category of microwave remote sensing microwave radiometers, in particular to a digital automatic compensation microwave radiometer. Background technique [0002] The output voltage of an ideal microwave radiometer can be expressed as: [0003] V out =G S ·(T' A +T REC )(1) [0004] Among them, T′ A is the signal temperature output by the microwave antenna; T REC is the equivalent noise temperature of the receiver itself; G S is the total gain of the system; V out The radiometer output voltage representing the temperature of the signal output by the microwave antenna. It can be seen from formula (1) that in order to guarantee V out Can accurately reflect T' A , to ensure the measurement accuracy of the microwave radiometer, it is necessary to make G S and T REC Always keep it constant. [0005] Since the birth of the microwave radiometer, in order to eliminate the system gain G S Due to the impact of...

AI Technical Summary

Problems solved by technology

Thus solving the system noise temperature T existing in the technical solution of "digital automatic compensation microwave radiometer" REC The influence of the noise temperature uncertainty caused by the antenna and feeder loss on the measurement accuracy of the radiometer, and further reduce the technical defects such as the size, weight and power consumption of the radiometer, as well as the long start-up stabilization time

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