3-Way call detection system
US7123704B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 14, 2005 |
| Grant date | Oct 17, 2006 |
| Priority date | — |
| Expiry date | Jan 14, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M3/56
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Disclosed herein is a three-way call detection system and method for detecting the addition of a third party to a pre-existing telephonic connection between a first party and a second party. The system comprises: a meter for measuring the amplitude of a line voltage of a telephonic connection between a first party and a second party, said line voltage having a frequency band F1; a first filter to remove a frequency band F2 from said line voltage and output a filtered signal, said frequency band F2 being a subset of F1; a white noise generator for generating a low level white noise signal with a frequency band that corresponds to F2 and with an amplitude that is significantly below an amplitude level of the measured line voltage for frequency band F2; a coupler for combining the low level white noise signal to the filtered signal, thereby outputting an additive line voltage; a second filter that passes only a portion of the additive line voltage, said signal that passes being referred to as the band-passed signal, said band-passed signal having a frequency range F3, said frequency band F3 being a subset of F1 and being inclusive of F2; and a processor for processing the band-passed …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.