Pass-by noise measurements are of growing importance in light of increasingly restrictive governmental regulations. This paper discusses a time-domain TPA method that allows identifying the pass-by noise contributions of the noise generating components such as the engine, exhaust, tyres etc. The core of the method is a power-based frequency-domain model representing the system in terms of noise sources and transfer paths. FRF measurements are required to identify the operational acoustic loads from near-field microphone recordings and propagate these to the pass-by target microphones on the two sides of the test track for subsequent positions of the vehicle. Once an adequate frequency-domain model is obtained, time-domain filters are constructed that allow synthesizing the loads and their partial contribution to the pass-by noise. An outdoor test campaign was carried out to validate the method. The tests were performed on a 4-cylinder vehicle. Several operational measurements were conducted including run-up and constant speed experiments in various throttles and gears. The obtained results were satisfying, revealing physically realistic noise source contributions up to 8 kHz.
