Stefanakis N., Sarris J.

A common problem in sound field reproduction is the need to estimate the transmission characteristics, usually formulated in a transfer matrix, between a set of sources and receivers within a closed space of random geometry where a closed form solution is not available. In this paper the Boundary Element Method (BEM) is used for the evaluation of the transfer matrix that relates the internal field pressures to the source excitation inside arbitrary shaped enclosures of known impedance boundary condition. So given a distribution of point sources inside an enclosure of known geometry the transfer matrix is evaluated applying the BEM and the optimal solution for the production of a desired sound field is then obtained by minimizing, in the least square sense, the difference between the reproduced and the desired sound field at a finite number of receiving positions. By defining a number of sensor positions greater than the number of source it is easy to reach to an over-determined system that can be solved by applying the SVD method. Simulation results for the production of a plane wave inside an L-shaped and a regular hexagon room are used to validate the feasibility of the process.