Spread spectrum phase locked loop with phase correction
US5003553A · kind A · utility
7Cited by
3References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 23, 1989 |
| Grant date | Mar 26, 1991 |
| Priority date | — |
| Expiry date | Aug 23, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03L7/193
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A global positioning system (GPS) receiver includes a phase locked loop that locks to the carrier signal from the GPS satellite at an offset frequency in order to recover the GPS data. The loop includes a phase shifter driven by a system clock through a synchronous clock inversion circuit. The phase of the system clock is periodically inverted synchronously with respect to the clock in order to compensate for the offset loop frequency so that the loop does not lose lock because of the offset error.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.