Signal generating circuit, optical signal transmitting apparatus, signal receiving circuit, method for establishing optical signal synchronization, and optical signal synchronization system
US8929750B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 2010 |
| Grant date | Jan 6, 2015 |
| Priority date | — |
| Expiry date | Jan 30, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/027
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus. Moreover, the optical signal receiving apparatus detects a clock offset between the optical signal receiving apparatus and the optical signal transmitting apparatus from an interval between the estimated frequency positions of the specific frequency band signals. Furthermor…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.