Multipath doppler adjusted frequency tracking loop
US6608858B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 26, 2000 |
| Grant date | Aug 19, 2003 |
| Priority date | — |
| Expiry date | Jan 26, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0087
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for frequency tracking is described. The present invention provides a tracking mechanism for removing the effects of error due to frequency offset as well as compensation for frequency error due to doppler in a plurality of multipath signals. Each finger of a RAKE receiver utilizing the present invention will compute a frequency error for that finger. The weighted average of all of these frequency errors is calculated and filtered to provide a control signal for varying the frequency of IF and RF frequency synthesizers, accounting for the common frequency offset seen at each finger. Additionally, each finger is equipped with a rotator for providing frequency adjustment specific to that finger. The frequency of each finger is adjusted through feedback of the frequency error for that finger.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.