ANALYTIC EXPANSION TECHNIQUE FOR AMBIENT-NOISE DIRECTIONALITY DETERMINATION

A new technique, based on the formation of the noise field, has been developed to determine ambient-noise directionality in relation to a line array. A computing algorithm is derived from the assumption that the cross-spectrum function of a noise field is analytic and can be expressed in terms of a superposition of plane waves. The angular resolution of the noise field obtained with this approach is not limited by the finite length of the array's aperture. A simulated noise field and actual sea data are used in illustrative examples for comparison with conventional methods. © 1979, American Association of Physics Teachers. All rights reserved.