Czyz K., Michalczyk M.

The paper concerns active noise control (ANC) systems creating 3-dimensional zones of quiet in enclosures. Electro-acoustic plants controlled by such systems are time-varying, what may be caused by changes of the air temperature and humidity or by any movements of persons in the enclosure. Adaptive control algorithms are applied to deal with these changes, what is widely described in the literature. However, the case when the time variations are caused by moving error microphone is hardly analysed. Adaptive control algorithms are used for calculating controller coefficients and dealing with changes of the electro-acoustic plant. For such tasks the adaptation is set to be slow. In case of the ANC systems with moving microphone adaptive control algorithms are used in a different way – the adaptation is set to be fast enough to track the movements of the error microphone. The paper presents results of preliminary real-world laboratory experiments demonstrating the behaviour of the ANC system with moving error microphone. It is shown that application of adaptive control algorithms allow a 3-dimensional zone of quiet to track the moving error microphone.