| 摘要 |
PROBLEM TO BE SOLVED: To prevent deterioration of accuracy in the measurement of a moving amount of a float body having a measuring device mounted thereon, in a method and a device for measuring river data such as river bottom profile (riverbed profile) or a flow rate of the river using an ultrasonic wave, particularly in the improvement of accuracy in measuring a moving amount and a moving direction of the measuring device. SOLUTION: The ultrasonic wave is transmitted at a prescribed time interval from an ultrasonic transmitter/receiver 301 to the direction of the river bottom. The ultrasonic wave scattered and reflected at the river bottom is received by a two dimensional ultrasonic detector 303 which is two dimensionally arranged. The intensity distribution and the phase distribution of the reflected wave from the river bottom is acquired by a signal processor 304 on the basis of the output of the two dimensional ultrasonic detector 303 corresponding to the two ultrasonic waves transmitted at a time interval from the ultrasonic transmitter/receiver 301. The correlation intensity between two intensity distributions and between phase distributions output from the signal processor 304 are acquired by a signal analyzer 305 as a function of moving distance, wherein among the two intensity distributions and the phase distributions, those corresponding to the ultrasonic wave emitted first approach the others. The moving distance having the maximum correlation intensity and the moving direction at that time are made as the moving distance and the moving direction of the measuring device between the two ultrasonic transmissions. COPYRIGHT: (C)2007,JPO&INPIT |
