Testing system for digital transmission lines
US5224149A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 26, 1992 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | Feb 26, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B3/46
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A testing system for digital transmission lines with a metallic loopback and direct current bypass for use with regenerative repeaters. The Bell telephone network typically includes transmit and receive lines interconnected to a central office. Regenerative repeaters positioned along the lines detect signals and regenerate new signals. The present invention includes a controller, loopback line, and bypass. The loopback line interconnects the transmit and receive lines upon receiving a test activation signal from the controller. The bypass allows direct current to pass through to the rest of the line during a test. Accordingly, when a test of the telephone lines is to be performed, lines will allow the test signal to loop back to the source of origin, but will block the loopback of DC power signals. Moreover, DC power is supplied to the rest of the transmission line, in the same manner as when the testing procedure is not occurring. Moreover, the loopback line is positioned such that the overload protection circuitry is also subject to the performance test.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.