Inverse Acoustic Wave Field Synthesis

Acoustic wave field synthesis is a method of sound reproduction of a primary sound source with the use of secondary sources, implemented as arrays of micro-speakers. This method is based on wave field theory. We have developed a finite element based scheme to solve this problem posed in an inverse setting. Huygens principle has been used to validate the method for a few simple problems. Huygen's principle suffers from the drawback that incorporation of sectondary sources at desired locations is rather difficult. We present a method for inverse acoustic wave field synthesis which overcomes the above limitation in the context of Two-Dimensional problems and show that incorporation of any geometric or material non linearities is relatively straight forward. This has significant implications for problems in geophysics or biological medium where material inhomogeneities are quite prevalent Numerical results are presented for sample problems in noise cancellation and wave field synthesis for inhomogeneous media. The method is capable of being extended to three dimensional problems involving dissipation and anisotropic medium and is a topic of continuing research.