Abstract: The acoustical nearfield comprehensive techniques are developed, which includes some new methods in finding out the best positions of reference microphone, identifying the incoherent sources, understanding the transmission paths of various incoherent source, evaluating the contribution of each source and predicting the output. The experiments and successful applications to studying vehicle exterior noise show that these new techniques are able to be used in the analysis of complex engineering system.

Key words: Acoustical holography, Acoustical nearfield, Experimental analysis, Noise Vehicle