CONVERSION METHOD OF HYDRAULIC WAVE TO SURFACE WAVE

PROBLEM TO BE SOLVED: To avoid a surface conversion from hydraulic wave with poor accuracy which occasionally appears by converting a hydraulic wave with large wave height to a surface wave by use of a surface wave conversion digital filter to determine the wave height, since an ultrasonic system cannot be generally used for high wave height because of breaking of waves. SOLUTION: A wave height is generally calculated by processing data for 20 minutes. Even if wave breakage occurs for the 20 minutes, a point where ultrasonic waveform is normally measured is present. The characteristic of the surface wave conversion filter is determined so that the waveform with the normal ultrasonic wave form is matched to a surface wave obtained by conversion from a hydraulic wave, and the hydraulic wave is converted to the surface wave by use of the determined digital filter. COPYRIGHT: (C)2006,JPO&NCIPI