Frame synchronization of an OFDM signal
US6928046B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 5, 1999 |
| Grant date | Aug 9, 2005 |
| Priority date | — |
| Expiry date | May 5, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2678
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Frame synchronization of a received OFDM signal (such as that used in a hybrid FM DAB system) is provided by filtering out significant outer frequency portions of the digital channels, and then using cyclic extension and correlation of the cyclically extended bits (or samples). The received OFDM signal is passed through a bandpass filter to remove outer digital subcarriers (i.e., those farthest from a center frequency) from a received OFDM signal before correlating to locate the OFDM frame boundaries. By filtering out digital subcarriers within each of the digital channels, particularly those closest to adjacent channels and thus most likely to be interfered with by an adjacent first channel OFDM (or FM) signal, correlation between cyclically extended bit (or sample) patterns and thus frame synchronization of OFDM signals can be improved significantly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.