System and method for obtaining clock recovery from a received data signal
US6009132A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 20, 1998 |
| Grant date | Dec 28, 1999 |
| Priority date | — |
| Expiry date | Mar 20, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L7/033
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system for the evaluation of a timing vector to determine whether reliable timing recovery may be established at a predetermined center frequency, or from a specific pilot tone in the received signal. According to the present invention, the timing vector is created using band edge filters, a pilot tone timing recovery band pass filter, or other suitable means. The timing vector is then sampled a predetermined number of times. The sampled timing vectors are plotted on a complex plane to evaluate the general distribution of the sampled timing vectors. Timing recovery is then established using an acceptable timing vector as determined by comparing the distribution of the sampled vectors with a predetermined distribution threshold. In particular, a narrow distribution indicates minimum of signal noise, interference, or disruption, whereas a wide distribution indicates the opposite. The instant invention also includes a means of evaluating the timing vector at several center frequencies in the case of band edge timing recover until an acceptable timing vector is found.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.