In conventional pass-by-noise tests, the vehicle noise emission levelisdetermined with amicrophone at aspecifieddistance from atest track while the vehicle drivesby. Although these tests offer asimple approach to assess the overall performance, theydonot yield information about the sources of noise distributed across the vehicle. Methods to determine the influence of local excitations can be useful for manufacturs attempting to apply an effective noise reduction treatment. Acoustic beamforming methods can be applied at high frequencies for moving structures to locate noise, butthey have difficulties quantifying the impact of each source on the sound pressure next to the test track. In this paper,amethod is presented to determine the sound pressure contributions using apanel noise approach based on direct measurements of particle velocity.The sound pressure contribution for separate car positions is calculated by combining the sound radiation and the acoustic transfer path. The time-averaged result, representing the sound radiated from avehicle driving by,isultimately obtained by spatially averaging the contributions at these positions. To validate the methodology,am easurement wasp erformed with as et of loudspeakers mounted on ac ar.T he measurement method and test results are presented, and the advantages and limitations of the novelmethod are discussed.

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