Analysis of the global reduction of broadband noise in a telephone kiosk using a MIMO modal ANC system

The possibility of implementation of ANC system for global reduction of broadband noise in a telephone kiosk application has been studied in this paper. By using a modal model of the acoustic environment of the enclosure the shape modes and their frequencies are obtained and suitable bandwidth for the controller design is calculated. Analysis shows that because of existing of some degenerate modes in this application, the control action is complicated. Simulation results show that how positions and number of loudspeakers and microphones will change the performance of the controller and its corresponding control effort. Based on these results and analysis a reasonable size for the controller and proper locations for sensors and actuators are proposed. Simulation results also show the effectiveness of the proposed system in reduction of the acoustic potential energy in the kiosk.