Distortion measurement in optical communication systems
US7606487B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 9, 2001 |
| Grant date | Oct 20, 2009 |
| Priority date | — |
| Expiry date | Oct 3, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/07953
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The distortion component of an optical signal received from an optical transmission system, such as an all-optical system, subject to noise and amplitude distortion components, can be evaluated by a method that utilises information derived from analysing the bit error ratio (BER) of the signal as a function of a movable threshold. The analysis is performed in high and low bit error ratio areas of the eye diagram used for data one/zero decision making. The intersections with the threshold axis (where BER=0.25) of extrapolations of the high and low bit error ratio values provide variables V1 and V2 which are divided (V1/V2) to obtain an estimate/prediction of the amplitude closure of the eye diagram resulting from amplitude distortion. The analysis is preferably carried out after Q conversion of the BER values. The method can also be extended to provide indications of Q, bit error ratio and optical signal-to-noise ratio within the signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.