Metallic channel unit network
US5202919A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 4, 1990 |
| Grant date | Apr 13, 1993 |
| Priority date | — |
| Expiry date | Sep 4, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/04
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A metallic channel unit network for interconnecting a two-wire, bidirectional signal transmitting means and a four-wire signal transmitting means in a communication system includes a voice hybrid driver, A/D signal processing circuit, D/A signal processing circuit, tip and ring switching drivers, and tip and ring sensing amplifiers. The metallic channel unit network is suitable for use with substantially all of the different alarm-signalling techniques utilized by the various alarm companies for connecting their equipment to a channel bank multiplexer coupled to the four-wire means. The metallic channel unit network provides an apparent metallic cable pair over the digital carrier in the frequency range of DC to 3.5 KHz with an amplitude variation between +200 to -200 VDC.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.