Traditionally, conventional polar response measurement of scattering from objects has been done using turntables and/or moving microphones and loudspeakers. In the current approach, near-field acoustic holography is used to measure the sound field above a scatterer. The scattered sound field is then spatially transformed to the desired distance and angle, corresponding to a certain angle relative to the normal of the surface. The method has been tested successfully on some scattering objects of interest, such as reflectors and diffusors in room acoustics. The method and assumptions are outlined in the paper. The advantages of the method suggested are primarily that the scattered sound field can be predicted also at various, close distances to the scattering object, and that the need for data storage is very much reduced compared to that of conventional polar response measurements.
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