Beamforming and Wavenumber Processing

Abstract

Planar nearfield acoustical holography (NAH) is a powerful experimental tool for studying and diagnosing noise radiation problems [1--11]. Based on measurements of typically sound pressure over a plane near the source, all sound field parameters can be calculated in any plane parallel with the measurement plane. In particular, the sound field can be mapped closer to the source than the measurement plane, which can provide very high spatial resolution of the source distribution. Since the calculation plane cannot in theory approach the source further than the nearest point on the source, planar NAH works best for but is not restricted to sources with a planar geometry.