HUFFMAN CODE-FED OMNIDIRECTIONAL ACOUSTICAL ARRAYS

The synthesis of linear and planar acoustical arrays of desired omnidirectional intensity patterns is considered. By relating the far-field sound intensity pattern to the correlation function of the used feeding sequence or code, it is shown that an almost omnidirectional pattern results when a code with a sharp autocorrelation function is used as the feeding sequence for the elements of the array. Huffman impulse-equivalent codes enjoy very sharp correlation properties, and are shown in this paper to result in good omnidirectional linear and planar acoustical arrays. The results have direct applications in underwater acoustical communication systems, public address systems, and acoustical measurements. © 1990 IEEE