抄録
Periodic noise radiated from two dimensional space between two square plates is controlled by active noise control. Noise source is put at center of the space and a control speaker is set at the same location. Filtered-X adaptive notch filter is used and the control system consists of the speaker and a microphone for control error detection. The noise source is sine wave sound or triangular wave sound and a period of the noise is known in the control. It is shown that the sufficient noise reduction is achieved for the controlled frequency component as well as in circumference of the square plates.
