Combined NAH and beamforming using the same microphone array

This article deals with the problem of how to design a microphone array that performs well for measurements using both Nearfield Acoustical Holography (NAH) and Beamforming (BF), as well as how to perform NAH processing on irregular array measurements. NAH typically provides calibrated sound intensity maps, while BF provides unscaled maps. The article also describes a method to perform sound intensity scaling of the BF maps in such a way that area-integration provides a good estimate of the sub-area sound power. Results from a set of loudspeaker measurements are presented.