音源探査の基礎的研究 : 単一音源の場合

抄録

If the source point of sound is found and reinforced, the vibration and the noise of a machine can be reduced. The delay time between the sound waves which arrive at two microphones is measured by using an FFT analyzer. From the delay time, the difference in the distances from the sound source to the two non-directional microphones is decided and the source is described as a point on a hyperbola. When one of the microphones is moved from d point to the other two points, other hyperbolas are found. The source point is thought to be the intersection of these hyperbolas. As some delay times are found in the cross correlation of these sounds which is the single sinusoidal wave, the differences in the distances are of several classes. Many intersections of three group hyperbolas exist. The center of the nearest points in these intersections agrees well with the sound source which is a loud speaker. This method can give the point of a sound source more simply than sound intensity method.