Loss of signal detection
US7941048B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 2007 |
| Grant date | May 10, 2011 |
| Priority date | — |
| Expiry date | Oct 8, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J14/0221
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
An apparatus and a method for accurately detecting Loss of Optical Power (LOS) by noise power cancellation effect and optical power is measured at two output ports of an athermal periodic filter, wherein one output port in the optical frequency domain, is aligned with the signal channels of an input WDM signal (on-grid port), whereas the second output port is aligned complementary to the first output port (off-grid port). In a preferred embodiment, the apparatus computes the ratio of the measured optical powers at the two output ports of the periodic filter, and comparing them to a threshold value that is determined from the overall common-mode rejection ratio (CMRR) of the detection apparatus. In an alternative embodiment, the apparatus additionally compares the optical power measured at the on-grid port to a threshold power that is determined from system design parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.