Passive intermodulation (PIM) measurements in common public radio interface (CPRI) spectrum analysis
US10892922B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 1, 2018 |
| Grant date | Jan 12, 2021 |
| Priority date | — |
| Expiry date | Nov 1, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/08
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A test device for detecting and measuring distance to passive intermodulation (PIM) is disclosed. The test device may comprise a receiver to receive a signal from a test point of a distributed cell site comprising a remote radio head (RRH) and a baseband unit (BBU) separated and connected via an optical feeder. The test device may also comprise a processor to detect passive intermodulation (PIM) and measure distance to the PIM (internal or external). For example, the processor may replace downlink IQ data in the signal with two-tone waveform IQ data, transmit the two-tone waveform IQ data to the RRH, and to monitor uplink spectrum to detect PIM, where the uplink spectrum may comprise uplink IQ data from the RRH. The processor may also perform uplink spectrum analysis using radio frequency (RF) monitoring, measure a time delay for the two-tone waveform and the detected PIM, and calculate a distance to the PIM based on the time delay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.