Digital quality index for QAM digital signals
US7792183B2 · kind B2 · utility
41Cited by
2References
25Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2007 |
| Grant date | Sep 7, 2010 |
| Priority date | — |
| Expiry date | Mar 2, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B17/21
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a system for calculating a digital quality index (DQI), which provides a rating on a predetermined scale, indicative of the impairments in a received quadrature amplitude modulated (QAM) signal in a CATV cable system. The DQI system utilizes bit error rates prior to and after forward error correction to calculate the DQI value. To increase the calculation rate, the bit error rates can be estimated using voltage errors, signal to noise ratios and/or average corner error metrics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.