System for measuring an eyewidth of a data signal in an asynchronous system
US7869544B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 2008 |
| Grant date | Jan 11, 2011 |
| Priority date | — |
| Expiry date | Jul 17, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/205
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An eyewidth of a data signal is determined by steps including: (a) recovering a phase of a clock from a data signal as a sampling clock; (b) shifting the phase of the sampling clock away from the first phase by a count multiplied by predetermined phase amount; (c) sampling the data signal with the shifted sampling clock phase to obtain sample data; d) determining whether the sample data contains error; (e) when the sample data does not contain error, recovering the phase of the clock from the data signal again for use as the first phase of the sampling clock, increasing the count value and repeating steps (b) through (e); and f) when the sample data contains error, determining the eyewidth based on the last shifted phase of the sampling clock prior to determining that the sample data contains error.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.