Abstract: The step sizes for tap positions of an adaptive filter (124) in an echo canceller (125) for canceling an echo signal are individually selected based upon a profile of the echo environment. A training signal (112) is injected into the echo canceller and to the echo path during a training interval, or period. The adaptive filter profiles the echo path during the training interval. Respective step sizes &agr;[k] for the tap positions are generated as a function of the echo profile so generated.

Abstract: A communications transmitter which operates as a mobile telephone incorporates a noise suppressor (100, FIG. 1) 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 to the force noise suppressor (100) to perform an update of a noise content estimate of the incoming voice signal.

Abstract: The step sizes for tap positions of an adaptive filter (124) in an echo canceller (125) for canceling an echo signal are individually selected based upon a profile of the echo environment. A training signal (112) is injected into the echo canceller and to the echo path during a training interval, or period. The adaptive filter profiles the echo path during the training interval. Respective step sizes &agr;[k] for the tap positions are generated as a function of the echo profile so generated.