Patent ID: 7092532

Claim:
An audio system for receiving a time domain input signal having an input frequency spectrum and for providing a time domain output signal, said audio system being adapted to remove a feedback condition within said time domain input signal, said system comprising: a) an analysis unit for receiving said time domain input signal and providing N bandpass input signals, each of said bandpass input signals corresponding to a portion of said input frequency spectrum, and wherein N is a positive integer; b) an adaptive feedback cancellation unit coupled to said analysis unit for receiving said N bandpass input signals and providing N bandpass output signals, said adaptive feedback cancellation unit comprising N sub-units, wherein at least one sub-unit is adapted to cancel feedback, the at least one sub-unit including: (i) a feedback detector coupled to said analysis unit for receiving one of said bandpass input signals and providing a feedback detection signal for indicating the presence of said feedback condition in said one of said bandpass input signals; (ii) an adaptive feedback canceller coupled to said feedback detector for receiving said feedback detection signal and providing an adaptive gain modification factor for adjusting gain when said feedback detection signal indicates the presence of said feedback condition within said one of said bandpass input signals; and, (iii) a multiplier coupled to said adaptive feedback canceller and said analysis unit for providing one of said bandpass output signals based on said one of said bandpass input signals and the adaptive gain modification factor; and, c) a synthesis unit for receiving said N bandpass output signals and for providing said time domain output signal.