Method and apparatus for attenuating engine generated noise.

摘要

A method and apparatus are described for attenuating harmonic noise components contained within noise generated by an internal combustion engine (10), based upon the rotation of the engine (10) during its operating cycle. A signal representing selected multiple harmonic noise components is generated from a table of values, based upon the engine rotation. This signal is adaptively filtered to produce a cancelling waveform, which is superimposed onto the engine noise to attenuate the selected multiple noise harmonics. The method and apparatus are useful for selecting and attenuating dominant noise harmonics produced at different engine speeds or by different types of engines, and the dominant harmonics of different forms of noise produced by the same engine. <IMAGE>