Active noise control at a moving location using virtual sensing

Abstract

A problem limiting the scope of practical local active noise control applications is that the zone of quiet created at the error sensor tends to be very small. This means that the error sensor generally needs to be positioned close to the location where control is desired, which might not always be a convenient or feasible solution. A number of virtual sensing algorithms have been suggested previously that can effectively move the zone of quiet away from the physical error sensor to a desired location that is spatially fixed. It is, however, very likely that the observer will move their head, which means thai the desired location of maximum attenuation will not be spatially fixed. A local active noise control system incorporating a virtual sensing method thus has to be able to create a moving zone of quiet that tracks the observer's ear. This paper presents a method for creating a moving zone of quiet that tracks a desired location based on a virtual sensing method called the remote microphone technique. The developed algorithm is implemented in an acoustic duct and experimental results are presented.© (2006) by the International Institute of Acoustics & Vibration.