Holographic Design of a Source Array Achieving a Desired Sound Field

Abstract

Where creating a desired complicated sound field, an acoustic source array should be designed appropriately in order to obtain the acoustic solace parameters To this end a method is suggested that will utilize an acoustical holography technique based on the inverse boundary-element method Acoustic analogy between the problems of source reconstruction and source design was the initial motivation for the study In the design of the source array the pressure distribution at specific field points is the constraint of the problem. and the signal distribution at the source surface points is the object function of the problem The whole procedure of the application consists of three stages First a condition of the desired sound field should be set as the constraint Second the geometry and the boundary conditions of the source array system and the target field, that is. points in the sound field or concern. ale modeled by the boundary elements Actual characteristics of source and space can be considered to generate an accurate condition of the target field. regardless of the near and fat fields Finally the source parameters are inversely calculated by backward projection The suggested method is especially useful in controlling the near and intermediate fields, and it can control the far field similarly to other methods As an example. a source array to fulfill the plane-wave propagating zone and another quiet zone near the propagation zone was designed and tested by simulation and measurement