| 摘要 |
PURPOSE:To take a measurement of distance regardless of environmental condition without obtaining environmental condition data by calculating the distance from the sound wave propagation time between two fixed points and the sound wave propagation time between two points whose distance is to be measured. CONSTITUTION:A controller 5 at one of two fixed points which are set at distance L1 sends an indication of measurement to a receiver 4, and an antenna 1 transmits a sounding command to the other antenna 14. Then, sounding from a transmitter 12 is detected by the receiver 4 to measure the sound wave propagation time t1. Similarly, the sound wave propagation time t2 between one fixed point and a moving body is measured through the receiver 4 and the transmitter 1 on the moving body to calculate the distance L to the moving body from L= L1X(t1/t2). Thus, the environmental condition data on many items including temperature are obtained to measure the distance through the simple constitution regardless of the environmental condition without perform correcting arithmetic, etc. |
