ASA 127th Meeting M.I.T. 1994 June 6-10

2aEA4. An algorithm for fast computing spatial array three-dimensional sound directivity.

Dehua Huang

Stephen Boucher

Airmar Technol. Corp., 69 Meadowbrook Dr., Milford, NH 03055

The ability to quickly predict spatial array radiation or receiver directivity is vital to acoustical array design, directivity synthesis, reflective wave cancellation by object active spatial (nonplanar surface) array, etc. A fast algorithm is developed to numerically simulate spatial array three-dimensional directivity, based on local element or subarray directivity and system spatial array directivity mapping technique. The spatial array is composed of a set of single elements or subarrays with an arbitrary weighting function. Further, the normal direction of the element or subarray active surface in the spatial array can be rotated in any direction in the system coordinates. Both theoretical derivation and mathematical approach are demonstrated. Numerical simulations and experimental verification of various examples are presented. The baffle effects due to finite baffle size and different backing materials of the array are considered by introducing a baffle function during the numerical simulation.