Active noise control with variable directivity loudspeakers

Active noise control (ANC) is an effective way to reduce the low frequency noise level for passengers in cars or aircrafts. In these applications, secondary sources are usually monopole loudspeakers. Variable directivity loudspeaker is a kind of loudspeaker which is able to control its own radiation directivity. It is potential to be able to control the sound field better compared monopole loudspeaker. Inspired by this, variable directivity loudspeakers are applied to an ANC system. A simulation is conducted to investigate the performance of the ANC system with variable directivity loudspeakers. Simulation results show that the ANC system with variable directivity loudspeakers outperforms the one with monopole loudspeakers in noise control using the same number of loudspeakers.