Method and configuration for forming a line termination of a telephone line
US5271059A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 1991 |
| Grant date | Dec 14, 1993 |
| Priority date | — |
| Expiry date | Jan 29, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M19/08
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
In a method and configuration for forming a line termination at two line terminals of a telephone line, alternating signals are separated from direct signals applied to line terminals, referred to a reference variable and added to a transmission signal from a transmission terminal to form a resultant actual-value signal. The resultant actual-value signal is compared with a reference signal at a gain-controlled amplifier. The reference signal is formed with an impedance transmission function corresponding to a given termination impedance by weighting the alternating signal at one of the line terminals being connected to a current sensor resistor. A current between the line terminals is determined with a control transistor associated with the current sensor resistor. The control transistor is controlled with the gain-controlled amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.