Wave direction measurement by a single wave follower buoy.

This paper describes a system for measuring the direction of ocean wave propagation , as well as wave height and period. The system employs a conventional wave-follower buoy, modified so as to provide compass, pitch, and roll signals in addition to the vertcal component of buoy accelerat[on. The modifications are indicated in the paper, and the buoy was used in rough water conditions in Narragansett Bay for a test. The pitch, roll, compass, and heave acceleration signals were all processed on the computer in the laboratory to provide a variety of results. This test condition was ideal in that the wind and wave conditions were changing steadily throughout the data recording process. The results presented in the paper include the wave height power spectral density, a polar tilt histogram for the buoy motion, and a family of polar plots of the average tilt angle in each 5SUP sector of azimuth of the buoy pitch/roll. (A)