Design of high directional broadband antenna for human body temperature measurement

In order to achieve higher temperature measurement accuracy and improve the requirement of radiation characteristics of the antenna, high directional small diameter antenna is designed for human body temperature measurement by microwave radiometer. The antenna frequency band is 6~12GHz, the gain is higher than 12dB, the diameter is more than 20dB, the maximum cross polarization level is less than -25dB, The E-plane and H-plane are symmetrically distributed, and the input standing wave ratio is less than 1.5dB. In this paper, the Angle horn size and directionality calculation formula were calculated to obtain the angle horn size, the ridge waveguide and ridge curve calculation formula were used to calculate, to obtain the dual-ridged horn size, and the modeling simulation in Comsol simulation software, to determine the optimal size. The simulation results of the broadband horn antenna show that the gain, backward and forward rejection ratio, standing wave ratio and other parameters are good, which is in line with the design objectives, and provides a solid foundation for further study of microwave radiometer temperature measurement.