摘要 |
A vibration/noise reducing device for applying contrary vibrations/sound waves whose phases are substantially opposite to vibrations/noises generated from an electrical apparatus is disclosed, in which the vibrations/noises from the electrical apparatus are sensed by a sensor, the sensed analog time-domain signal is A/D converted, the resulting digital time-domain signal is then Fourier-transformed, the resulting Fourier-transformed digital frequency-domain signal is modified in its amplitude/phase to produce a second digital frequency-domain signal for generating a vibration/noise reducing control signal, the second digital-frequency-domain signal is inverse-Fourier-transformed, the resulting inverse-Fourier transformed second digital time-domain signal is D/A converted, and the resulting analog time-domain signal is used as the control signal to generate the contrary vibration/sound waves to be applied to the vibrations/noises. |