Method and apparatus for detecting frame delimiters in Ethernet passive optical networks with forward error correction
US9450705B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 1, 2010 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | Jun 7, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0045
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Embodiments of the present invention provide a system that identifies an even delimiter in a forward error correction (FEC)-coded Ethernet frame. The system receives an FEC-coded Ethernet frame that includes the even delimiter, which is a predetermined sequence that separates a conventional Ethernet frame and FEC parity bits in the FEC-coded Ethernet frame. Next, the system scans a bit stream of the FEC-coded Ethernet frame. Then, the system determines a first Hamming distance between a first consecutive set of frame bits in the bit stream and the even delimiter. The system also determines a second Hamming distance between a second consecutive set of frame bits in the bit stream and the even delimiter. Both the first and second Hamming distances are shorter than a predefined value. The system subsequently selects one of the first and second sets of frame bits having the shorter Hamming distance as the even delimiter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.