Automatic frequency control for a wireless communication system with multiple subcarriers
US8009775B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 9, 2006 |
| Grant date | Aug 30, 2011 |
| Priority date | — |
| Expiry date | May 11, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/0007
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Techniques for performing frequency control in an OFDM system are described. In one aspect, frequency acquisition is performed based on a received pilot, and frequency tracking is performed based on received OFDM symbols. For frequency acquisition, an initial frequency error estimate may be derived based on the received pilot, and an automatic frequency control (AFC) loop may be initialized with the initial frequency error estimate. For frequency tracking, a frequency error estimate may be derived for each received OFDM symbol, and the AFC loop may be updated with the frequency error estimate. Frequency error in input samples is corrected by the AFC loop with the initial frequency error estimate as well as the frequency error estimate for each received OFDM symbol. In another aspect, a variable number of samples of a received OFDM symbol are selected, e.g., based on the received OFDM symbol timing, for use for frequency error estimation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.