CONTROLLER FOR NOISE IN VEHICLE

摘要

PURPOSE:To prevent oscillation resulting from an additional sound generated from an additional sound source and inputted to a noise detection means by separating noise due to the additional sound source generated in a vehicle and noise from other sources than the additional sound source and obtaining a noise control signal based on a transfer function with the noise control signal supplied to the additional sound source. CONSTITUTION:A microphone 1 detects noise caused by a speaker 7 and noise caused by other device than the speaker 7 and inputs the result to an adaptive filter 5. The adaptive filter 5 uses noise po(t) and a speaker drive voltage v(t) to separate the noise ps(t) caused by the speaker 7 from the po(t) to calculate a system impulse response h(t) between the speaker drive voltage v(t) and the noise ps(t) by the speaker 7. A phase correcting circuit 11 is used to make the phase of the noise (additional sound) generated from the speaker 7 opposite to that of the in-vehicle noise other than the speaker 7 and the amplitude equal to each other. Thus, the quiet state in the vehicle is improved.