Apparatus and method for frequency offset monitoring used in digital coherent optical receiver
US8103177B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 2009 |
| Grant date | Jan 24, 2012 |
| Priority date | — |
| Expiry date | May 13, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B10/63
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention discloses a frequency offset detecting apparatus and method for use in a digital coherent optical receiver. The digital coherent optical receiver comprises: a front-end processing section for generating a digital baseband electric signal; an equalizer for performing equalized filtering on the digital baseband electric signal; and the frequency offset detecting apparatus for detecting frequency offset contained in the digital baseband electric signal or frequency offset contained in a signal outputted by the equalizer; wherein the frequency offset detecting apparatus comprises an argument difference obtaining unit, a first subtracter, a second subtracter, a quantizer and an averager, of which the argument difference obtaining unit obtains an argument difference of adjacent symbols in a signal inputted therein; the first subtracter subtracts an output of the averager from the argument difference obtained by the argument difference obtaining unit; the quantizer performs uniform quantization with predetermined intervals on an output of the first subtracter; the second subtracter subtracts an output of the quantizer from the argument difference obtained by the argu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.