Patent ID: 6999920

Claim:
A method of reducing at least one of echo and noise signals in telecommunications systems for transmitting useful acoustic signals, comprising: determining by silence detection when a mixture of useful signals and interference signals contains a speech signal or when a silence interval is present; and varying, by means of a two-input multiplier, the amplitude of the useful signals, which are generally disturbed by the at least one of echo and noise signals, in response to a time-dependent control signal a 0 (t) or a control signal a 0 (k) clocked at a sampling rate f T =1/T, where k ∈ denotes the number of samples, and T denotes the period from one sample to the next, wherein the control signal a 0 (t) or a 0 (k) is varied in such a way that, in the presence of speech signals in the useful signals, the amplitude of the control signal a 0 (t) or a 0 (k) is set to a predetermined constant value c 0 , wherein, from the beginning of a silence interval in the useful signal, the amplitude of the control signal a 0 (t) or a 0 (k) is continuously reduced from one sample to the next according to the recursion formula a 0 ( k+ 1)= a 0 ( k )·β, where β<1, and wherein, after the end of a silence interval, a 0 (k) is set equal to c 0 .