A novel beamformer array design for noise source location from intermediate measurement distances

Abstract

Very regular beamformer array geometries will have grating lobes in their directivity pattern when applied above a certain frequency. The grating lobes can be suppressed by removing periodicities, typically by the use of random arrays or spiral arrays. Large irregular arrays are, however, difficult to build due to their complicated support structure and cabling. The present paper describes a novel array design, which maintains the low grating lobe level of irregular arrays, but which has a regularity that allows a much simpler support structure and cabling. The performance is compared with that of comparable regular and irregular arrays, and verified through practical measurements. Examples of application to the localization of source of wind noise and high-frequency engine noise will be presented.