Digital timing recovery
US4010323A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 29, 1975 |
| Grant date | Mar 1, 1977 |
| Priority date | — |
| Expiry date | Oct 29, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/0331
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Sample timing recovery in a differentially coherent phase-shift keyed data transmission system is accomplished through the use of digital techniques. Samples of received phase-modulated signal waves taken at a rate high with respect to the carrier frequency are applied to a delay medium advantageously implemented by a shift register. Stored samples spaced by known carrier phase differences are compared for the purpose of detecting phase changes. Digital indications of such phase changes resulting from differentiation of comparator outputs are then effective to control a phase-locked oscillator and provide a substantially jitter-free timing recovery wave without using excess bandwidth for the transmitted wave.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.