Patent ID: 6138040
Filing Date: 2000-10-24
Classification: H04M

Abstract:
A method for suppressing speaker activation in a portable communication device operated in a speakerphone mode, comprising the steps of:receiving an outbound audio signal from a wireless source;determining that the outbound audio signal does not contain speech information;muting the speaker;receiving an inbound audio signal at a microphone of the portable communication device;vocoding the inbound audio signal to provide an inbound vocoded signal comprising of a succession of frames, each frame of the succession of frames having a frame energy value and a background noise value;calculating an average background noise value for each frame of the succession of frames;calculating a staggered average value of the frame energy;comparing the staggered average value of the frame energy with the average background noise value;determining that speech is present in a given frame of the succession of frames if the staggered average value of the frame energy is sufficiently greater then the average background noise value; andpreventing activation of the speaker while performing the step of determining that speech is present in the inbound audio signal while, subsequent to performing the step of determining, detecting speech information in the outbound audio signal.