CORRELATION BASED FILTER ADAPTATION

摘要

Example apparatus and methods concern performing stereo acoustic echo cancellation using a correlation based filter adaptation control approach and without using stereo de-correlation. An embodiment includes a stereo adaptive filter that produces an echo removed microphone signal from received audio signals. The embodiment includes a mono adaptive filter that produces an echo removed microphone signal from the received audio signals. A correlation detector determines a level of correlation between the received signals and provides a signal to an adaptive filter controller. The adaptive filter controller controls how the stereo adaptive filter and the mono adaptive filter adapt audio echo cancellation as a function of the correlation between the received signals. A signal selector may select for output the signal from either the stereo adaptive filter or the mono adaptive filter based, for example, on the power level of the signals.

主权项

1. A system for performing stereo audio echo cancellation, comprising:
a stereo adaptive filter configured to receive a microphone signal and two channel speaker signals, the two channel speaker signals being received, respectively, from two separate speakers and to produce an echo removed microphone signal based on the microphone signal and the two channel speaker signals, where the stereo adaptive filter is configured to mitigate audio echo associated with the two channel speaker signals; a mono adaptive filter configured to receive the microphone signal and the two channel speaker signals and to produce a second echo removed microphone signal based on a mixture of the two channel speaker signals, where the mono adaptive filter is configured to mitigate audio echo associated with the two channel speaker signals; a correlation detector configured to receive the two channel speaker signals and to determine a level of correlation between the two channel speaker signals; and an adaptive filter controller configured:
to selectively alter how the stereo adaptive filter adapts audio echo cancellation filtering based, at least in part, on the level of correlation between the two channel speaker signals, andto selectively alter how the mono adaptive filter adapts audio echo cancellation filtering based, at least in part, on the level of correlation between the two channel speaker signals.