NOISE SUPPRESSION USING EXTERNAL VOICE ACTIVITY DETECTION

摘要

A communications transmitter which operates as a mobile telephone incorporates a noise suppressor (100) which reduces the background noise in the transmitted voice signal. An external voice activity detector (150), which operates in conjunction with a noise suppressor (100) estimates the signal power of the incoming voice signal and compares this to an estimated noise floor. As a result of this comparison, a voice activity factor is applied to an updated noise floor estimate to create a voice activity threshold estimate. The voice activity threshold estimate is then used to decide whether or not the force noise suppressor (100) to perform an update of a noise content estimate of the incoming voice signal.