Detecting Self-Generated Wake Expressions

摘要

A speech-based audio device may be configured to detect a user-uttered wake expression and to respond by interpreting subsequent words or phrases as commands. In order to distinguish between utterance of the wake expression by the user and generation of the wake expression by the device itself, directional audio signals may by analyzed to detect whether the wake expression has been received from multiple directions. If the wake expression has been received from many directions, it is declared as being generated by the audio device and ignored. Otherwise, if the wake expression is received from a single direction or a limited number of directions, the wake expression is declared as being uttered by the user and subsequent words or phrase are interpreted and acted upon by the audio device.

主权项

1. An audio device configured to respond to a trigger expression uttered by a user, comprising:
a speaker configured to generate output audio; a microphone array configured to produce a plurality of input audio signals; an audio beamformer configured to produce a plurality of directional audio signals based at least in part on the input audio signals, wherein the directional audio signals represent audio from respectively corresponding directions relative to the audio device; one or more speech recognition components configured to detect whether the predefined expression occurs in the audio represented by each of the respective directional audio signals; and an expression detector configured to (a) determine that the trigger expression has been uttered by the user if the trigger expression occurs in the audio represented by less than a threshold number of the directional audio signals; and (b) determine that the predefined expression has been not been generated by the speaker if the predefined expression occurs in the audio represented by all of the directional audio signals.