Simplified timing correction for data despreading of serial offset quadrature pulse-shaped spread signals
US7609755B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 21, 2005 |
| Grant date | Oct 27, 2009 |
| Priority date | — |
| Expiry date | Nov 21, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/712
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A simplified timing correction method is provided for data despreading of serial offset quadrature pulse-shaped spread signals. The simplified timing correction algorithm is applied to a rake receiver for improved performance in a multi-path channel. Serial formatting of the spreading modulation waveform is selected to reduce the SYNC/serial probe correlation complexity. The method includes the steps of: (a) decimating serial inphase (I) and quadrature (Q) signals to form decimated I and Q even samples and decimated I and Q odd samples; (b) obtaining an autocorrelation profile of a spreading sequence used by the receiver; (c) detecting a synchronization starting point using the I and Q even samples; and (d) deciding to either move, or not move, the synchronization starting point, based on the autocorrelation profile obtained in step (b). Step (d) decides to move the synchronization starting point, and uses the I and Q odd samples for subsequent despreading of the I and Q signals. Step (d) also decides not to move the synchronization starting point, and uses the I and Q even samples for subsequent despreading of the I and Q signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.