Patent ID: 7664243
Filing Date: 2010-02-16
Classification: H04M

Abstract:
1. A system for detecting addition of a third party to a pre-existing telephonic connection between a first party and a second party, said system comprising: a meter for measuring an amplitude of a line voltage of the telephonic connection between the first party and the second party, said line voltage having a frequency band F a first filter to remove a frequency band F a random noise generator for generating a random noise signal having a frequency band corresponding to said frequency band F a coupler to combine said random noise signal with said filtered signal, thereby outputting an additive line voltage; a second filter that passes at least a portion of said additive line voltage, including at least a portion of said frequency band F a processor for time-domain monitoring of an amplitude of said band-passed signal for a shift associated with addition of the third party to the pre-existing telephonic connection.