Abstract:Principles of Passive Intermodulation(PIM) production and its control method are introduced. After mainly researching and applying the PIM control technologies for the feed chain of multibeam antenna in high throughput satellite, including optimal design of high isolation of feed system, flange face choke of feed unit, PIM source control of feed array mounting plate, low PIM design of Ka-band PIM test system, etc., a Ka-band multibeam antenna achieves the goals that the 7th order PIM performance of the feed unit is controlled to ≤-135 dBm at temperatures between -60 ℃ and +100 ℃，and the performance of the feed array is controlled to ≤-140 dBm at normal temperature. The application of the product demonstrates the validity of the proposed technology for PIM control, which is of benefit to high performance antenna design.