Planar nearfield acoustic holography is usually based on narrow-band, single frequency analysis, which is time consuming when the source behavior over a broad frequency range is of interest, as is the case with many industrial sources. In the present paper a method, broadband planar nearfield acoustic holography based on one-third-octave band analysis (BPNAH), is developed, of which data concerning the complex band pressure on the hologram is obtained by the combination of the one-third-octave band mean-square pressure and the phase of the pressure corresponding to a single frequency line. A numerical study shows that there is no noticeable difference between the quality of the reconstruction by the BPNAH method and the quality of the conventional reconstruction, which is based on the summation of one frequency by one frequency in the corresponding band, even in the presence of noise. Further analysis shows this procedure can be extended to a source consisting of a set of fully correlated points, of which the primary points are all close together and other relatively secondary points can be far away from the former points. This method is a simple, time-saving and robust technique and thus particularly adapted to industrial studies.
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