Systems and methods for rapid uplink air interface synchronization
US8259777B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 2007 |
| Grant date | Sep 4, 2012 |
| Priority date | — |
| Expiry date | Sep 1, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W52/42
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Rapid uplink synchronization is enabled by reducing a 2D search problem to two 1D search problems, which can generally be performed in less time. Advantage is taken of fact that a mobile device sends a ranging code on multiple sub-carriers. Using the assumption that adjacent sub-carriers will have approximately equivalent channel characteristics, phase ambiguity can be removed by differentially combining pairs of adjacent sub-carriers. Once the phase ambiguity is removed, the code, timing, and power level may be determined relatively quickly. In one embodiment, the values of correlations between received signals and possible codes are compared with a threshold.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.