Optical coherent receiver, frequency offset estimating apparatus and method for optical coherent receiver
US8078066B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2008 |
| Grant date | Dec 13, 2011 |
| Priority date | — |
| Expiry date | Jun 7, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/63
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention discloses an optical coherent receiver, and a frequency offset estimating apparatus and a frequency offset estimating method for use in the optical coherent receiver. The optical coherent receiver includes a front end processing section for changing an optical signal into a base band digital electric signal. The frequency offset estimating apparatus comprises a phase offset calculating section, for calculating a phase offset in said base band digital electric signal; a phase offset change calculating section, for calculating a change of said phase offset, namely a phase offset change, in accordance with the phase offset calculated by said phase offset calculating section; an ambiguity deciding section, for deciding whether there is ambiguity in said phase offset change calculated by said phase offset change calculating section, and outputting the phase offset change having no ambiguity; and a loop filtering section, for acquiring a weighted average of the phase offset change outputted by said ambiguity deciding section.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.