Analog line connection
US5091703A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 19, 1990 |
| Grant date | Feb 25, 1992 |
| Priority date | — |
| Expiry date | Nov 19, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/22
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An analog line connection circuit provides that the transmission voltage is not superimposed on the received voltage given a data transmission in duplex operation via a two-wire line. The line connection circuit is provided with an amplifier that comprises two symmetrical outputs, the first of these outputs being connected via a first ohmic connecting resistor to a first terminal of a first winding of a transformer and the second output being connected via a second ohmic connecting resistor to a second terminal of the first winding of the transformer. The transformer comprises a second winding connected to a transmission line. A series circuit of a first auxiliary resistor, a complex impedence and a second auxiliary resistor is connected between the outputs of the amplifier. The two ohmic voltage dividers are respectively arranged cross-connected between a terminal point of the first winding of the transformer and a junction of an auxiliary resistor with the complex impedance, the received voltage being output at the outputs of these ohmic divider resistors for a receiver unfluenced by the transmission voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.