ASA 128th Meeting - Austin, Texas - 1994 Nov 28 .. Dec 02

3aPAa15. New fast field programs for a multiple-source system.

Y. L. Li

Dept. of Elect. and Comput. Eng., Univ. of Illinois, Rm. 332, 3rd fl. North CSRL, 1308 W. Main St., Urbana, IL 61801

Michael J. White

U.S. Army Construction Eng. Res. Lab., Champaign, IL 61826-9005

A new fast field program (FFP) has been developed for numerical computation of sound pressure from a phased multiple-source or multiple-receiver system in a layered medium. The new FFP is based on a far-field approximation. Using the stationary phase method, the twofold integral for sound pressure in the far field is reduced to a onefold integral. The onefold integral makes the new FFP very efficient and more practical than computation performed individually for each source. A criterion for validity of the far-field approximation is also given. The sound pressure of several phased-array systems in a layered medium has been computed. Numerical results from the new FFP are compared with some well-known results. The agreement is excellent.