Character Analysis and Realization of Small Microwave Calibration Source Based on Cone Array

Abstract

During the use of radiometer, antenna calibration is an indispensable step. In this paper, the calibration source is designed for human body temperature measurement calibration. So, the calibration source should have the close to 1 emissivity in 12-18GHz and have good temperature uniformity. To achieve the above two requirements, a small and high-precision and temperature controllable blackbody calibration device is designed. In this paper, the electromagnetic scattering characteristics and temperature distribution uniformity of blackbody calibration source is analyzed. The cone model design is determined by simulation. During the simulation, it is found that increasing the coating thickness does not significantly improve the emissivity under small-scale and large elevation. Finally, a calibration source is realized. Under the working frequency band, the emissivity is higher than 0.998. And the maximum surface temperature distribution error is only $2 ^{\circ}\mathrm{C}$ in $100 ^{\circ}\mathrm{C}$ situations.