Real-Time Reporting of Broadband Wave Directional Spectra by NDBO Buoys

An improved system for the measurement and telemetry of ocean wave directional spectra has been developed by the NOAA Data Buoy Office (NDBO). Based on the conventional technique for obtaining an azimuthal approximation of the directional spectrum from time series of measurements of the motion of a pitch/roll buoy, the system represents improvements in hardware over an earlier experimental system tested by NDBO, which demonstrated the feasibility of real-time reporting of directional spectra. The improved system was installed and operated on board the 12-meter-diameter discus-hull buoy XERB, (experimental environmental research buoy), to verify the improved system concept. Experience gained with the improved hardware will be reflected in the development of an operational system specification. An improved onboard processing procedure, employing a technique based on the segmented-record fast Fourier transform, will soon be installed aboard XERB for operational verification.