| 摘要 |
PURPOSE:To improve the measuring accuracy of a sound wave by arranging three or more sound wave detectors in a polygon shape and adopting a value that is measured by a pair of the detectors existed where a sound wave incident angle is nearest to 90 degrees out of angles of sound arriving directions measured at each pair of sound wave detectors. CONSTITUTION:Each output of each pair of sound wave detectors 1 and 2, 2 and 3 and 3 and 1 is inputted to arithmetic circuits 4-6 and the angle of the sound wave arriving direction is calculated. And same three angles out of six angles of the sound wave arriving directions which are obtained at the arithmetic circuits 4-6 are extracted at an arithmetic circuit 7. Furthermore, a corresponded sound wave incident angle which is nearest to 90 degree out of angles extracted at the arithmetic circuit 7 is extracted at an arithmetic circuit 8 and the angle which has the smallest absolute difference value between three sound wave incident angles and 90 degrees is selected and is displayed on a display device 9. |
