Passive intermodulation (PIM) distance to fault analyzer with selectable harmonic level
US8410786B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 2011 |
| Grant date | Apr 2, 2013 |
| Priority date | — |
| Expiry date | Nov 7, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/11
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A distance to PIM measurement circuit is made using a device such as an AWS transceiver that has separate transmit and receive bands. With a typical AWS transceiver placed in close proximity to a PCS transceiver, the AWS device will include a band reject filter to eliminate interference from the PCS signals. The PIM measurement circuit includes two frequency sources F1 and F2 that are provided through a combiner for characterization of the PIM circuit. To enable distance determination, an FM measurement is created by using a offset sweep generator attached to one of the two frequency sources. To avoid frequencies blocked by the band reject filter, a desired harmonic of a test PIM harmonic signal is selected outside the band of the band reject filter. In one embodiment, a reference signal is provided by mixing a signal from an xM multiplier connected to the F1 source with an xN multiplier signal connected to the F2 source, the mixed output being filtered to select the desired harmonic reference signal to avoid the band reject filter. In another embodiment, a reference signal is created by generating all harmonics of the combined F1 and F2 signal using a series connected amplifier an…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.