Howling suppression device

Abstract

Abstract PURPOSE:To reestimate an impulse response at every interruption of an input signal to a microphone and to contrive the constantly stable howling suppression by using a signal immediately before the input signal to the microphone is interrupted as a signal for outputting from a speaker at the time of estimating the impulse response. CONSTITUTION:An impulse response estimating circuit 2 receives a timing from a power calculating circuit 3 and then, estimates the impulse response between the speaker 5 and the microphone 6 by using a learning identification method from the output of a buffer circuit 1 and the output of the microphone 6. After the estimation is completed, the convolution operation of the impulse response and the output of the buffer circuit 1 is carried out to falsely form a feedback signal 9, it is subtracted from the output of the microphone 6 to have the output. The power calculating circuit 3 constantly calculates the power of the output of the microphone 6 and detects the time when the power goes to zero and outputs a buffer contents output start and an impulse response estimation start signal 10 to the buffer circuit 1 and the impulse response estimation circuit 2. Thereby, the constantly stable howling suppression effect is obtained.

Inventors

• 👤 Yukihiro Fujimoto
• 👤 幸広 藤本

Bibliographic Details