Considerations upon the Characteristic Frequency Spectra of some Road Transportation Means

The noise generated by the road transportation means is characterized by frequency spectra, acoustic pressure levels and their variations in time. The sources of vibration and noise depend on the transportation mean type. Therefore every transportation mean identifies itself by characteristic frequency spectrum and noise level. Using the recording of the frequency spectra of the transportation means, one can identify the attenuation methods of the generated noise. In this paper we present some results obtained in the study of the noise generated by the road transportation means using the frequency spectra.