Design and verification of thermal infrared automatic brightness temperature radiometer

Abstract

In order to meet the requirements of high precision automatic measurement of surface brightness temperature, which is used for in-orbit calibration and product verification of infrared remote sensor, the design and verification of field thermal infrared brightness temperature radiometer are studied. The difference and compensation method is used to obtain the radiance of the ground target. First, the thermopile detector is used to measure the target and the background respectively for difference, and then the standard platinum resistance is used to improve the measurement accuracy. The optical spectrum of 8~14 μm, 8.2~9.2 μm, 10.3~ 11.3 μm, 11.5~l2.5 μm is achieved by the optical spectrum and rotation of the filter wheel, and the photoelectric amplification and acquisition are realized by the high-precision pre-amplification and acquisition circuit. After the radiometer is developed, radiation calibration based on the surface source blackbody is carried out, and the temperature measurement is compared with the laboratory water blackbody. The deviation of measurement is less than 0.14K. The field thermal infrared bright temperature radiometer was compared with thermal infrared radiometer CE312 in the field, and the average deviation of the two devices was less than 0.12K, which verified the feasibility and rationality of the temperature measurement method.