Abstract:In ground communication systems, microwave components of the base station are exposed in air for a period of time, usually influenced by temperatures, humidity, pollution and other factors. The original clean surface of the components is oxidized and contaminated, leading to poor contact and Passive Intermodulation(PIM), which interferes with the communication system. Therefore, PIM is inevitable in ground mobile communication system. In the satellite communication system, due to the long communication distance and platform limitation, the common transceiver mode should be adopted. As the receiver sensitivity increases, the requirements on PIM indexes are more strict. PIM is one of the key problems for realizing the high reliability of system. The characteristics and research progress of PIM interference in ground mobile communication and satellite microwave components are introduced, which can provide a reference for PIM research.