Decision feedback equalizer in an OFDM WLAN receiver
US7340000B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 2004 |
| Grant date | Mar 4, 2008 |
| Priority date | — |
| Expiry date | May 30, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2025/03414
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
In an OFDM radio receiver for a wireless packet network, an apparatus to equalize a presently received OFDM signal containing subcarriers using an equalizing signal formed from the past symbols of subcarriers. The apparatus includes a subtractor to subtract the equalizing signal from the present signal, a DFT device to convert to subcarriers, a forward processor to correct the subcarriers for the channel and phase errors, a decision device to make decisions for the subcarriers, a reverse processor to corrupt the decision-based subcarriers' phase in the same manner as the forward processor corrects the subcarrier's phase, an inverse DFT device to form a time signal from the reverse processed subcarriers, and a feedback filter to generate the equalizing signal. The feedback filter's impulse response is directly calculated from an estimate of the channel response.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.