Evaluation of system configuration to check the suitability for the sound field rendering using the inverse approach

Abstract

Sound field control by the inverse approach based on the acoustical holography is useful to render an arbitrary target sound field within a selected control zone if the target condition is given in a detailed format. This method needs information on the various factors constituting the total system: source array configuration, relative position of source and control region, assigning method of target field condition, conditioning method, etc. Because these factors heavily affect the accuracy of the generated sound field, a proper definition of the problem including all factors related to the system configuration is important. In this work, the method to evaluate the suitability of system to achieve the target sound field was investigated in the viewpoint of efficiency and precision. Because the difference between target and generated sound field strongly depends on the noise and the information error existing in the actual situation, the expected accuracy should be calculated in relation to the characteristics of system transfer matrix. To this end, variances of uncorrelated noise, condition number, and linear independency of the transfer matrix are evaluated to check the suitability of transfer matrix for accurately rendering the sound field with different types of array system. © 2013 Acoustical Society of America.