Line impedance matching using dynamically generated transfer functions
US6185280A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1998 |
| Grant date | Feb 6, 2001 |
| Priority date | — |
| Expiry date | Feb 12, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/42314
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A system and method for determining the impedance of a telephone transmission line are disclosed. A test signal is transmitted through a telephone switch to the telephone line and corresponding echo signals are monitored. The test and echo signals are correlated to derive an impulse response. A transfer function for the system is calculated from the impulse response. Then, a transfer function for the transmission line is derived using the system transfer function and the transfer function of the telephone switch. Finally, the transmission line impedance is calculated from the transmission line transfer function. Once the transmission line impedance is known, an impedance matching circuit for the telephone switch can be modified to match the transmission line and the switch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.