Identifying directions of acoustically reflective surfaces

摘要

An audio device may be configured to produce output audio and to also capture input audio for speech recognition. Beamforming may be used to produce directional audio signals that emphasize sounds received from different directions. Acoustic echo cancellation (AEC) may be used to remove components of output audio from the directional input signals. AEC may be implemented by an adaptive filter based on dynamically optimized filter coefficients. The filter coefficients may be analyzed to detect the presence of potentially problematic reflective surfaces near the audio device. When such a reflective surface is detected, the user may be notified by illuminating a directional indicator on a housing of the audio device, where the directional indicator indicates the direction of the potentially problematic surface relative to the audio device.

主权项

1. An audio device, comprising:
a housing; a speaker to generate output audio; multiple microphones to produce input audio signals; one or more audio beamformers configured to produce multiple directional audio signals from the input audio signals, wherein each of the directional audio signals potentially contains one or more acoustic echoes of the output audio, and wherein each of the directional audio signals emphasizes sound received from a corresponding direction relative to the audio device; one or more visual indicators, the one or more visual indicators being controllable to visually indicate different directions relative to the audio device; one or more acoustic echo cancellers configured to cancel the one or more acoustic echoes from the directional audio signals based at least in part on sequences of dynamically updated filter coefficients; a proximity detector configured to perform acts comprising:
analyzing the sequences of dynamically updated filter coefficients to identify one of the directional audio signals that contains an acoustic echo originating from a nearest of one or more acoustically reflective surfaces; andcontrolling the one or more visual indicators to indicate the direction of the nearest of the one or more acoustically reflective surfaces.