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Technology evolves at a rapid-fire pace. That’s why we’ve built an easy-to-use glossary to help you better understand the terms, technologies and trends that impact your business.

External passive intermodulation (PIM)

There are two types of passive intermodulation (PIM): external and internal. External PIM differs from internal PIM as the former is caused by objects located near cell sites such as metallic objects (usually rusty) close to the antenna. With external PIM, technicians must hunt down and pinpoint the source (or sources) causing the interference.

Troubleshooting either internal or external PIM can be an expensive, manual process. When PIM is external, the process is similar to radio frequency (RF) interference hunting, where a technician is dispatched onsite and uses a RF spectrum analyzer to pinpoint the source. The process of interference hunting is highly manual and typically requires expertise in the area of RF.

Read about internal PIM

Learn more:

Infographic: RF spectrum in today’s 5G world

Success story: How a 5G operator quickly isolated and resolved RF interference issues

Blog: 5G rollout challenges and considerations

Discover EXFO’s solutions:

5GPro Spectrum Analyzer: RF spectrum analyzer

iORF: Intelligent RF Spectrum Analysis over CPRI

FTB 5GPro: complete, all-in-one 4G and 5G test solution