Abstract: For the irregular temperature field caused by the multiple conditions of reflector antenna and the change of solar directon, temperature field can be described as a function of the angle between sunlight and aperture plane, based on which, a method of estimating temperature field in real-time is presented. A thermal analysis model is founded and a temperature data sheet is built by calculating the temperature fields under different angles between sunlight and antenna aperture plane. According to current working condition, corresponding temperature field can be obtained by looking-up the temperature data sheet, performing rotation, and being corrected by the measuring temperature values. For this engineering problem, one 7.3 m reflector antenna operated in Ka band is considered as a research object, and the simulation temperature and the measuring temperature are estimated both with good agreement with the estimated temperatures. The analysis results show that the proposed method is simple, fast and effective, and can be used for the real-time compensation for the thermal distortion. There is also reference value for the antenna structure design.

Key words: reflector antenna, temperature estimation, temperature experiment, thermal model