The MNO’s RAN performance team noticed that the operations support system (OSS) flagged the presence of an RF noise issue in the network based on high uplink (UL) received signal strength indicator (RSSI) levels.
In order to take a closer look and attempt to diagnose the problem, a maintenance team visited the site to collect RF spectrum over CPRI traces. The team used auto-PIM detection in the OpticalRF application to identify the presence of PIM issues, based on the value of the slope in the spectrum. (Initially, since the PIM reading was less than 5 dB, a value under the MNO’s threshold of 6 dB, PIM was not flagged as a potential problem.)
Due to the degradation in KPIs, the EXFO team became involved—supporting the MNO in further investigating the source of noise causing the degradation. Once PIM issues were confirmed, the challenge became how to quickly and efficiently determine whether PIM was internal or external, pinpoint the root cause of interference and swiftly move forward with corrective action.

The post EXFO Case Study: Tier 1 MNO uses EXFO solutions to quickly isolate and resolve RF interference and PIM issues appeared first on RCR Wireless News.