Thermal Design and Thermal Reliability Analysis of SAR Antenna System Unfolding

The SAR antenna system is a core component of the Qilu-1 microsatellite payload. The successful unfolding of the feed source and reflecting surface is the basic prerequisite for the normal operation of the payload. The temperature of the joints connected with them as the primary unfolding criterion are directly related to the success or failure of the antenna system. Therefore, thermal design and thermal reliability analysis are needed. In this paper, the thermal control of the feed source joint is designed and the circuit reliability is analyzed. The key parameters that affect the temperature of the reflecting surface joint are considered and the predicted temperature is simulated. The predicted temperature uncertainty of the reflecting surface joint is calculated, the optimal unfolding stage and thermal reliability are analyzed. The unfolding process of the antenna system is designed and the response times are tested or simulated. Finally, the antenna system unfolded successfully as expected in the orbit. This paper can be used as a reference for the thermal design and reliability analysis of other small SAR antenna systems.