High resolution intensity measurements using a new technique

Abstract

Long-wavelength acoustical holography can be used to reconstruct images of sound sources which radiate into the farfield, but these images are generally assumed to be limited in resolution by the wavelength of the radiated sound. A new technique based on holographic principles has been developed with no intrinsic resolution limit. Thus, high resolution images of sound sources are obtained irregardless of the wavelength. The technique involves the recording of the sound pressure amplitude and phase with a plane array of microphones, then exactly reconstructing digitally the intensity of the sound sources with a computer and displaying the results with computer graphics. Thus, one can identify the location and intensity of multiple sound sources.