OFDM pilot tone tracking for wireless LAN
US7551677B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Aug 6, 2003 |
| Grant date | Jun 23, 2009 |
| Priority date | — |
| Expiry date | Jan 20, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0087
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A pilot phase tracking loop for an OFDM receiver including a phase rotator receiving an incoming signal, a fast Fourier transform coupled to a phase rotator output, and a pilot phase error metric including a discrete Fourier transform portion coupled to the phase rotator output. The pilot phase error metric determines a phase error estimate associated with a received OFDM symbol, e.g., a data symbol, from the phase rotator output. A loop filter is coupled to the pilot phase error metric output and an oscillator is coupled to the loop filter output. The oscillator output is coupled to the phase rotator to adjust the phase of subsequent OFDM symbols of the incoming signal. Phase noise introduced by a radio portion of the OFDM receiver and OFDM transmitter is reduced by the baseband portion of the OFDM receiver improving OFDM signal tracking under poor SNR conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.