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G. Szekely:
"Vergleich akustischer Messmethoden für den Straßenverkehr";
Supervisor: E. Pucher; E 315 Institut für Verbrennungskraftmaschinen und Kraftfahrzeugbau, 2002.

This diploma thesis attempts a survey of the different acoustical measuring methods for the external noise measuring of personal motor vehicles for different driving modes and measurement sites.
Aim of this work was to give an arrangement of the methods with the following error considerations inclusive evaluations regarding the equipment. The discussed measuring methods are partly standardized procedures, partly not standardized methods for the purposes of research and development.
At the beginning of this work acoustical terms, reasons of noise emergence and the development of noise limit values for motor vehicles were described.
Afterwards followed the analysis of the researched procedures. The statistical pass-by and the close proximity method for examination of the influence of road surfaces on the noise emergence and spreading according to ISO 11819-1 and 2; the pass-by noise measurement for vehicle type-approval (ISO 362),supplemented with a procedure for analyzing tractive force caused rise of the tire noise level; the roll-by measurement, based upon the EU-directive 92/23/EWG,
and the trailer drive-by method, developed by the TÜV Automotive, for
determining noise emission from car tires; measurement methods on acoustic chassis dynamometer, such as the in-door pass-by measurement, and procedures in aero-acoustical wind tunnels for observing the automobile wind noise; and the near-field measurement for controlling the exhaust noises as well, were considered.
The measurement principle, trial-execution, evaluation and the needed
instrumentation were detailed. Correspondingly the possible uncertainties in cause of the environmental and background noise influences, further on deviations through the measurement devices as well, were illustrated.
The methods were finally compared in respect of measuring sites, equipment,time spent and results.