High acuity sound-source localization by means of a triangular spherical array

Sound source localization systems typically measure differences in time-of-arrival between pairs of microphones in free field arrays. Using a different concept, we previously designed and built a localization system that mimics nature\´s solution of harnessing wave diffraction about the head while relying only on two sensors positioned antipodally. One of its important advantages is the generation of intensity difference information, in addition to time/phase differences. This sensor configuration is limited, however, by its intrinsic axial symmetry. Here I depart from the constraint of two sensors while retaining the advantages of a diffracting "head", by introducing a symmetric array of three microphones placed equidistantly on a diffracting sphere. Detailed computations reveal that this design is capable of superior broadband localization of 1° resolution in the plane of the microphones. Experimental work is under way to verify these calculations.