Spread spectrum alignment repositioning method
US5457713A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 7, 1994 |
| Grant date | Oct 10, 1995 |
| Priority date | — |
| Expiry date | Mar 7, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/7085
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method for maintaining spread spectrum chip sequence synchronization, over arbitrary time periods, without the use of traditional closed loop strategies. The technique can be accomplished entirely in software or with the addition of a minimum of electronic components. The receiver periodically forces a chip code reposition optimization to jog the receiver-chip sequence into a high level of synchronization after some period of time in which the receiver's chip sequence alignment has run open loop with respect to the transmitter-chip sequence embedded in the received spread-spectrum signal. The reposition technique allows the use of very low cost crystals for the chip sequence generator time base in both receiver and transmitter, and also provides time cues in which to optimize time-of-flight radio position fixes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.