Quadratic phase coupling analysis for infrasound vehicle detection

The low attenuation characteristic of infrasound enables it to propagate long distances making it possible for the detection of infrasound sources. In this paper, a comparison in terms of the detection range between an acoustic microphone and an infrasound sensor in the context of vehicle detection is made. We propose to employ the bispectrum based quadratic phase coupling (QPC) analysis to extract characteristic frequencies of the vehicle signal. These frequencies can subsequently be used to detect the presence of the vehicle in order to evaluate the sensors´ detection range. Experimental results show that the QPC outperforms the power spectrum estimation method for vehicle detection. In addition, it is found that the infrasound sensor outperforms the microphone in terms of vehicle detection range under the same test condition.