Active control of broadband noise using fuzzy logic

The author explores the use of fuzzy logic for the active control of broadband noise, as an alternative to more conventional linear filter approaches. A simple example is chosen in which a compact random noise source is radiating into free space. The simulated control is provided by a canceling noise source in the form of a loudspeaker placed between the primary noise source and a location in the far field where the noise reduction is desired. The peak cross correlation between the signals from an early microphone placed near the noise source and an error microphone in the far field is used as the error function. The results obtained demonstrate that fuzzy logic performs well in actively controlling broadband noise for the cases shown, achieving significant noise reduction levels in a reasonably fast and stable manner