US Patent 8345850 System and method for detecting three-way call attempts

Embodiments of this disclosure include methods in which a three-way call attempt is detected. Methods include monitoring the active communications of a telephone management system for pulses of energy indicative of a three-way call. A Fast Fourier Transform (FFT) is computed for each pulse of energy with time domain characteristics consistent with a click. Phases of each component for the pulse are also analyzed. If the phases are generally linear (i.e., if the phases have a common group delay or phase delay), then the pulse is a three-way call click and appropriate action (e.g., monitoring the call, terminating the call, warning the caller, etc.) is initiated.