CONSIDERATION ON INPERFECT MODEL OF BOUNDARY CONDITION FOR SOUND FIELD CONTROL BY THE IN- VERSE APPROACH

Unlike in an exterior space, to render a desired sound field in an interior space, the reverberant field induced by the walls should be considered. However, perfect identification of the boundary condition for every reflector in the space is difficult in a real situation, therefore approximations are generally adopted to simulate the acoustical characteristics in a room. In this work, the application of a source array configuration that can maintain the performance despite the input noise and deviation of boundary conditions is investigated as an alternative method to perfect modelling of wall reflection condition. Because the inefficiency of the source system is an important reason for instability, an efficient source configuration and optimized solution with low power consumption can make the solution robust. This solution which the redundancy is minimized is also robust to the modelling of error which is included in the transfer matrix because of the perturbation theory. Here, the effectiveness of the selection method based on the linear independence of matrix elements is applied to select an efficient source configuration to control a sound field in an interior space. The simulation results show that this method can achieve a sound field that is relatively robust to both the noise of the input signal and the modelling error of the boundary condition.