| 摘要 |
PROBLEM TO BE SOLVED: To provide an active noise control system and a method thereof capable of highly accurately performing noise reduction control by feedforward control without using an error microphone, improving a processing speed, and simplifying the system.SOLUTION: The active noise control system includes a measurement microphone 3 for measuring noise Q, a controller 6 for creating and outputting a control sound S for reducing the noise, and a control speaker 9 for releasing the control sound. The controller includes: a bandpass filter 6a for transmitting only frequency components of a control object frequency band of the noise; an adaptive filter 6b for estimating a control object predominant frequency from the frequency components transmitting through the bandpass filter; and a control signal arithmetic part 6c that executes a phase correction of a phase delay with respect to the control object predominant frequency by time control on the basis of the phase delay for each frequency of the premeasured controller and creating a control sound with an inverse phase. |
