Active noise reduction device, active noise reduction system using the same, mobile device, and active noise reduction method

摘要

The reference signal generation unit of the active noise reduction device of the present invention outputs a reference signal correlated with vibration to the adaptive filter unit. The filter coefficient update unit receives the error signal and sequentially updates the filter coefficient of the adaptive filter unit. The error signal is generated by a canceling sound based on the output of the adaptive filter unit and noise. The detection unit detects the filter coefficient of the filter coefficient update unit, and determines the output level of the adaptive filter unit. Then, the amplitude of the canceling sound is adjusted based on the output level of the adaptive filter unit estimated by the detection unit.