Impedance adapter for network coupler cable
US5771262A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 1996 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Sep 19, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/28
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The invention provides an impedance adapter that automaticaly switches to impedances that match network transmit/receive lines impedances (105,106) by a controlled switching of various impedances mounted serially/parallely with connected transmitter/receiver (100,101). For a high speed adapter, a balanced transmitter/receiver is required for limiting crosstalk effect due to the high transmission rate. Transmit/Receive impedance adaptation networks (102-103) are composed of serial/parallel networks of resistors and relay contacts that are switched independently by magnetic coils of an impedance switching circuit (110) and having values conformable to the various network impedances imposed by different national regulations. By using the principle of double deviation voltage technique, a measuring circuit (108) detects upward and downward voltages (VA,VB), VB amplified by 2 to generate an analog signal VS (VS=VA-2VB) to a control logic circuit (109). This circuit (109) determines if the resistors value selected by the magnetic coils of said impedance switching circuit (110) is equal or not equal to the impedance of the network lines (106,105). Thus, it compares VS to a voltage Vref (2…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.