Carrier recovery in communications system
US6031880A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1996 |
| Grant date | Feb 29, 2000 |
| Priority date | — |
| Expiry date | Jul 2, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0046
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method of carrier recovery in a wireless communications system using a known synchronization word, for example an IS-54 TDMA system, operates in two stages to produce an estimate of carrier phase. In the first stage, a complex fading factor, embodying carrier phase information, is estimated from the synchronization word in the received signal using a least square criterion. In the second stage, the carrier phase is estimated from this complex fading factor by averaging. The averaging can provide a recursive average or a moving average, or can be implemented using Kalman filtering which also provides an estimated amplitude factor and frequency shift. The method and apparatus provide a substantial improvement over phase locked loop carrier recovery.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.