Method and arrangement for automatic frequency control in a communication system
US8014475B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 17, 2004 |
| Grant date | Sep 6, 2011 |
| Priority date | — |
| Expiry date | Jun 28, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0081
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An arrangement (900), method and unit for AFC in a communication system (100) having: a frequency estimator (980) producing a decision-directed frequency estimate from a received signal; and an AFC loop receiving the decision-directed frequency estimate and performing therewith frequency control. The AFC process may use a CRC-decision directed frequency estimate as the final stage in a multi-stage AFC process (preceded by SCH- and midamble-derived frequency estimate stages), such that a verified received data sequence is used to re-construct a local copy of the ideal received data symbols expected at the output of a detector. This local copy is then correlated with the actual detector output and the results used to estimate the frequency error present on the received signal. The AFC process is inherent suited for discontinuous receive (DRX) applications. This provides the advantage of allowing required frequency correction accuracy to have minimal impact on the error rate of the received data in various channel configurations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.