Passive 3rd order Intermodulation occurs when multiple high-power signals interact with non-linear components, creating additional frequencies that raise the noise level. The factors contributing to PIM include junctions where current doesn’t increase linearly with voltage, which can result in interference, thus compromising system reliability and data rates.
Passive Intermodulation testing offers a lens into the quality of interconnects, especially when standard measurements might overlook issues. As the satcom industry typically tests the magnitude of the third harmonic by deploying two 20 W signals onto the RF interconnect, achieving a PIM level of -153 dBc is considered the benchmark. Addressing PIM involves ensuring proper tightening of connectors, selecting appropriate materials, and eliminating non-linear contacts. Issues like loose parts, rough surfaces, oxidation, and residual flux can exacerbate PIM, so understanding and managing these factors are crucial.
Examples
The Beam Forming Network Products illustrated below are a few examples of the many types delivered units.
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