一种新型透波低无源互调温箱箱体的设计

收发共用技术在卫星通信天线上的广泛应用将引发无源互调（passive intermodulation, PIM）。卫星天线工作在空间高低温交变环境中，而其PIM性能对温度具有敏感性，故需开展地面试验予以验证。为此，提出一款可用于测试天线在高低温环境下PIM性能的透波低无源互调温箱，主要在透波材料选用、结构耐压、箱体保温性能等方面开展设计和验证，最终建造的温箱满足耐温-150～150 ℃，箱体结构聚甲基丙烯酰亚胺（PMI）板的安全裕度为0.648，总插损＜1 dB，箱体的PIM性能基本稳定优于-150 dBm，目前已广泛应用在天线PIM性能的地面试验验证中。

Design of a new-type wave-transparent temperature test box with low passive intermodulation

The wide application of the transmitter-receiver sharing technology in the satellite communication antenna brings about the inevitable passive intermodulation (PIM). For the satellite antenna operating in high and low temperature environment in the space, whose PIM performance is sensitive to the temperature, and the ground tests are needed to verify the antenna’s PIM performance. Based on this requirement, a new type of wave-transparent test box is designed, with which the antenna can be tested for its PIM performance at high and low temperatures. The box is designed mainly in terms of the dielectric material selection, the structural pressure resistance, and the thermal insulation performance. The test verification shows that the box can stand the temperature range of -150 ℃ to 150 ℃, with a safety margin of 0.648 of the PMI board of the box structure, and the total insertion loss is less than 1 dB. The PIM performance of the box body is basically stable and better than -150 dBm. and it can be widely used in the ground validation test for antennas’ PIM performance.