Passive intermodulation (PIM) in broadcast transmission systems-lessons learned and a look into the future

摘要

Passive Intermodulation (PIM) occurring in worldwide broadcast systems has only received a very small amount of attention. This paper will focus on how and where PIM occurs in broadcast systems. Known PIM sources occurring in broadcast equipment are reviewed. PIM interference examples are provided for an ATSC DTV transmitter interfering with adjacent channel receivers. Both “static” and “dynamic” PIM categories with example levels are discussed. PIM research and lessons from the cellular industry are applied to broadcast components. Further research and areas to be investigated are suggested for future development.