Line impairment display for digital modems
US4639934A · kind A · utility
16Cited by
9References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1985 |
| Grant date | Jan 27, 1987 |
| Priority date | — |
| Expiry date | Apr 11, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/206
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A modem receiver used in a QAM or PSK data communication system is provided with various circuits generating error or monitoring signals indicative of the status of the system. These signals and the in-phase and quadrature components of the received signals are fed to an interface circuit which generates display signals suitable for driving a display unit such as an oscilloscope. These display signals define an image composed of the signal constellation of the received signals and various error or monitoring points.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.