Method and apparatus for coupling a voiceband modem circuit to a common phoneline connector
US6597768B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 14, 2001 |
| Grant date | Jul 22, 2003 |
| Priority date | — |
| Expiry date | Sep 12, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/066
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for coupling a voiceband modem circuit to a common phoneline connector, the common phoneline connection having a ring line connection and a tip line connection which couples a ring/tip line pair to a subscriber loop circuit, the voiceband modem circuit operating in a voiceband modem operating frequency band and having a voiceband modem interface ring line and a voiceband modem interface tip line. The voiceband modem interface ring line is coupled to the ring line and the voiceband modem interface tip line is coupled to the tip line connection by inserting, between the ring line connection and the voiceband modem interface ring line and between the tip line connection and the voiceband modem interface tip line, a series pair of inductors. A first inductor of the series pair has a low inductance and a high self-resonant frequency and a second inductor of the series pair has a high inductance and low self-resonant frequency. The low inductance, the high self-resonant frequency, the high inductance and the low self-resonant frequency are each determined to locate a filtering cutoff point between the voiceband modem operating frequency band and a digital subscribe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.