Measuring method of a wide range level and an apparatus thereof

Abstract

A method for measuring the water level of a reservoir, a larger river and an underground water and an apparatus thereof comprises a waveguide tube selected in a predetermined length, on the upper portion of which a sonic pulse generator is mounted, and a plurality of sonic receivers (first, second, third . . . nth), such as a microphone, arranged at an interval l from each another, in which the sonic pulse generator generates sonic impulses in a predetermined period, the receivers receive impulses divided into advancing waves and reflecting waves in turns, these impulses are amplified/wave-shaped to be applied to a microprocessor, and the microprocessor measures the time interval t.sub.1 between the advancing wave and the reflecting wave received by first sonic receiver and the time interval t.sub.n-1 between first sonic receiver and the n-1th sonic receiver located close to the water surface so as to calculate the water level L. Also, when the water level L is measured on the slope surface of a reservoir, a larger river, etc., a ball type float is inserted in the waveguide tube. In order to measure the water level of the underground water, a supporting rod, which has a plurality of sonic receivers (first, second, third . . . nth) are fixed at a predetermined interval l, is inserted into an underground water observing tube instead of the waveguide tube.