Active noise reduction device, vehicle, and active noise reduction method

An active noise reduction device comprising:

• a reference signal input that receives a reference signal outputted by a reference signal source and having a correlation with noise in a space in a vehicle, the reference signal source being attached to the vehicle;
• a simulated vibration transfer characteristics filter unit that generates a second signal by correcting, using simulated vibration transfer characteristics, a first signal for outputting, from a loudspeaker attached to the vehicle, a sound different from a canceling sound for reducing the noise, the simulated vibration transfer characteristics simulating vibration transfer characteristics from the loudspeaker to the reference signal source;
• a first subtracter that outputs a corrected reference signal obtained by subtracting the second signal generated, from the reference signal received by the reference signal input;
• an adaptive filter unit that applies an adaptive filter to the corrected reference signal outputted from the first subtracter to generate a canceling signal to be used to output the canceling sound;
• a canceling signal output for outputting the canceling signal generated to an outside;
• an error signal input that receives an error signal corresponding to a residual sound resulting from interference between the canceling sound and the noise;
• a first simulated acoustic transfer characteristics filter unit that generates a third signal by correcting the first signal using first simulated acoustic transfer characteristics that simulate acoustic transfer characteristics in the space;
• a second subtracter that outputs a corrected error signal obtained by subtracting the third signal generated, from the error signal received by the error signal input;
• a second simulated acoustic transfer characteristics filter unit that generates a filtered reference signal by correcting the corrected reference signal using second simulated acoustic transfer characteristics that simulate acoustic transfer characteristics in the space;
• and
• a filter coefficient updater that updates a coefficient of the adaptive filter using the corrected error signal outputted and the filtered reference signal generated.