Estimation of direction of infra sound by music method

摘要

This paper describes the estimation of direction of infrasound arrival by the MUSIC (MUltiple SIgnal Classification) method. We can feel an existence of the sound from the vibration of the pane and the shake of furniture. The distance attenuation of the sound is less than one of audio sound. We observed the infrasound generated by the power machine used for manufacturing gravel. A basic frequency of the measured sound waves is 14Hz, and the sound level is about 120 dB at a position 100m apart from the sound source. We estimate direction of arrival of the infrasound wave with a linear microphone array, which is composed of three microphones, and the each spacing is 11m. It is possible to estimate the propagation direction within 10-degree accuracy by the MUSIC method.