Method and apparatus for attenuating an unwanted signal in a mix of signals

摘要

Apparatus for attenuating an unwanted signal, eg. a speech signal, in a mix of signals, eg. a broadcast audio signal, includes an adaptive cancellation circuit 30 having an adaptive transversal filter 32 controlled in accordance with the circuit output. The apparatus is provided with a delay measurement system 10 for measuring the delay between the unwanted and mixed signals and for controlling the appropriate one of two variable delays 21 and 22 so as to approximately co-time the unwanted signal and the contribution of the unwanted signal which is in the mixed signal. The adaptive filter can thus be made significantly smaller.