Method of determining a start of a transmitted frame in a frame-based communications network
US6993101B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2001 |
| Grant date | Jan 31, 2006 |
| Priority date | — |
| Expiry date | Apr 13, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/50
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method of determining a start of a transmitted frame at a receiver on a frame-based communications network. A received transmitted frame is filtered using filter coefficients matched to a preamble symbol sequence to provide a correlation sequence. The correlation sequence is low-pass filtered and delayed to provide a delayed low-pass filtered correlation signal. The delayed low-pass filtered correlation signal is compared with the low-pass filtered correlation signal and a fixed predetermined threshold to provide a correlation difference indicator. Energy of the received transmitted frame is detected and the energy is low-pass filtered to provide a low-pass filtered energy signal. The low-pass filtered correlation signal is compared with the low-pass filtered energy signal to provide a correlation peak indicator. A logical-AND of the correlation difference indicator and the correlation peak indicator is formed to determine a match/no match comparison indicative of the start of a transmitted frame.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.