Although the Beamforming for moving sources is applied successfully to locate and to analyze noise sources at airplanes and trains, there are only a few papers where this technique is applied to cars. The present paper deals with the methodology that is neccessary to perform pass-by measurements on cars using microphone array technique and beamforming algorithms. In a first step, simulations were performed to determine the parameters required to carry out the intended measurements. Based on the results from the simulations, a 56-microphone array with 28 additional microphones, located on 8 external arms attached to the center array, was chosen because it obtained better noise source separation than other arrays evaluated. This array should be located at a distance of 5 m of the pass-by line, with a vertical distance of 1.5 m between the center of the array and the gound in order to separate the noise source from its image source. To process the data obtained from the measurements a moving focus algorithm was chosen, as it obtained better noise source separation than the fixed focus algorithm. The evaluation of the spectra showed a common spectrum trend independent from the tyre. This trend consists of a peak around 1 kHz with a decrease of the sound pressure level when the frequency is increased. Through the noise source maps the location of the noise source was calculated in the pass-by of the car near the center of the tread, identifying also higher emission from the front of the tyre than from the rear. A comparison between the results from the present study with those from other researches found in the literature shows a good agreement. Thus, it is possible to conclude that the methodology proposed is suitable for noise source identification during the pass-by of cars.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Methodology for pass-by measurements on cars with beamforming




    Publication date :

    2014


    Size :

    18 Seiten, 16 Bilder, 22 Quellen



    Type of media :

    Conference paper


    Type of material :

    Storage medium


    Language :

    English




    Pass-By Noise Source Identification for Railroad Cars using Array Measurements

    Graf, Hans Rudolf / Czolbe, Christian | DataCite | 2019


    One-Pass Pricing Methodology

    Gray, James / Garcia, Tina | SAE Technical Papers | 2002


    Digital interpolation beamforming for low-pass and bandpass signals

    Pridham, R.G. / Mucci, R.A. | Tema Archive | 1979


    Robust superdirectional beamforming for hands-free speech capture in cars

    Mabande, Edwin / Schad, Adrian / Kellermann, Walter | Tema Archive | 2009


    Passenger Vehicle Pass-By Noise Test Using Generalized Inverse Beamforming

    Arruda, José R. F. / Janssens, Karl / Zavala, Paulo A. G. et al. | SAE Technical Papers | 2011