Method and apparatus for synchronising receivers
US7515663B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2002 |
| Grant date | Apr 7, 2009 |
| Priority date | — |
| Expiry date | Jun 3, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2656
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A receiver produces complex data samples from a demodulated received signal. The data samples, which may form a preamble identifying a wireless LAN data burst, are arranged in a sequence comprising sub-sequences having a predetermined relationship with each other. A tuning frequency offset is determined by delaying the complex data samples by a plurality of different delay periods, auto-correlating the complex data samples using said different delay periods in order to produce respective auto-correlation outputs, determining a plurality of phase-dependent values each dependent upon phase errors in a respective auto-correlation output and calculating a value representing frequency offset by combining the phase-dependent values in a weighted manner. The preamble can be recognised by using the same delay means. One matched filter is used to detect a particular sub-sequence, the output is fed to the delay means, and a second matched filter receives the outputs of the delay means to detect sub-sequences having the correct timing relationship.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.