Thermal Analysis of Digital Transceiving Unit (DTU) for 400 kg-Class Communication Satellite Considering On-Orbit Environment

Low Earth Orbit(LEO) communication satellites have emerged as a key technology driving the evolution of global communications technology, owing to their capacity for high data transmission rates and extensive coverage area. In the field of communication satellites, there is an increasing demand for enhancement in payloads, with the objective of performing real-time data processing capabilities. This necessity has given rise to the densification of the high heat generating Electrical, Electronic and Electromechanical(EEE) parts. This causes the junction temperature of the EEE parts to rise, which has devastating effects on the performance, lifetime, and reliability of the payloads. Ultimately, the entire satellite system can lead to mission failure, so thermal design with prior thermal analysis and testing is required. In this study, a steady-state thermal analysis of the digital transceiving unit(DTU) of a payload for a LEO communication satellite was performed in the on-orbit environment. DTU is highly integrated with high-performance EEE parts due to its mission to relay communication signals on communication satellites. During the mission, the temperature distribution of the EEE parts under the worst cold and hot conditions was verified to ensure that the temperature requirements of the DTU were met. Furthermore, derating analysis of temperature was conducted to assess the thermal stability and reliability of EEE parts.