FEEDBACK CANCELING SYSTEM AND METHOD

摘要

Reducing feedback in an input signal that contains a signal component based on an output signal from a proximate output. The input signal is separated into a plurality of frequency bands by band pass filters. The power of signal in each band is determined, and the band signal with the greatest power is selected. That band's signal is sampled at a sampling rate, and at regular intervals one of the samples is selected. Blind signal separation is used to estimate signal sources from the selected samples. The estimated signals are compared to the output signal, and the estimated signal most similar to the output signal is subtracted from the input signal.

主权项

1. A system for reducing feedback, comprising:
an output device operative to emit an output signal; an input device operative to receive an input signal that is a composite of a plurality of component signals, wherein at least one of the component signals is based on the output signal; a plurality of band pass filters coupled to the transducer, operative to separate the electrical signal into a plurality of respective frequency bands; a power analyzer coupled to the band pass filters and operative to determine the power of the electrical signal in each of the frequency bands and select a band in which the signal therein has the greatest power; a signal sampler coupled to the power analyzer and operative to sample the selected band's signal at a sampling rate and select one of the samples at regular intervals; a blind signal source (BSS) estimator coupled to the signal sampler and operative to estimate one or more signal sources from the selected samples; and an acoustic echo canceller (AEC) coupled to the BSS estimator and operative to:
compare an estimated signal of each of the estimated signal sources to the output signal;select an estimated signal most similar to the output signal; andsubtract the selected estimated signal from the input signal to form a desired signal.