Patent US 5,583,943

An active noise elimination apparatus for eliminating noise generated from a blower by generating from a sound generation unit a sound which offsets the noise, in a cooling system for cooling a heat source by air blown from the blower and exhausted to an exhaust port of the system through a duct, includes a first sound reception unit for receiving the noise generated from the blower; a first simulation unit for outputting a sound to the sound generation unit simulating the noise generated from the blower and transmitted to the exhaust port through the duct; a second simulation unit for receiving as input a noise simulating signal of the first simulation unit so as to simulate a detouring sound generated from the sound generation unit and transmitted to the first sound reception unit through the duct; and a subtraction unit for subtracting the detouring sound simulating signal of the second simulation unit from the noise signal received by the first sound reception unit and outputting the result to the first simulation unit.