3-Way call detection system and method
First Claim
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1. A three way call detection system for detecting the addition of a third party to an pre-existing telephonic connection between a first party and a second party, said system comprising:
- 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 at least 3 db below an amplitude level of the measured line voltage for frequency band F2, a coupler for combining the low level white noise signal with 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 signal and determining a baseline amplitude level associated with a two-way call;
wherein said processor monitors the band-passed signal in the time domain for a shift in baseline amplitude level, which shift is associated with the addition of a third party to the telephonic connection.
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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.
91 Citations
20 Claims
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1. A three way call detection system for detecting the addition of a third party to an pre-existing telephonic connection between a first party and a second party, said system comprising:
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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 at least 3 db below an amplitude level of the measured line voltage for frequency band F2, a coupler for combining the low level white noise signal with 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 signal and determining a baseline amplitude level associated with a two-way call;
wherein said processor monitors the band-passed signal in the time domain for a shift in baseline amplitude level, which shift is associated with the addition of a third party to the telephonic connection. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
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20. A method of detecting the addition of a third party to an pre-existing telephonic connection between a first party and a second party, said method comprising:
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measuring a line voltage for amplitude, said measured line voltage having a frequency band F1;
filtering the measured line voltage to remove a frequency band F2 to create a filtered signal, said frequency band F2 being a subset of frequency band F1;
generating a low level white noise signal with a frequency band that corresponds to F2 and with an amplitude that is at least 3 db below an amplitude level of the measured line voltage for frequency band F2, adding the low level white noise signal to the filtered signal to create an additive line voltage;
filtering the additive line voltage to pass 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;
processing the band-passed signal to determine a baseline amplitude level associated with the characteristics of a two-way call;
monitoring the band-passed signal in the time domain for a shift in baseline amplitude level, which shift is associated with the addition of a third party to the previous two-party call.
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Specification