On the Analysis of Measured Output from Model Test : A New Estimating Method of Almost Sine Periodic Wave Components Disturbed by Noise

Abstract

This report relates to the analysis of measurement data with periodicity, such as those of model tests carried out to investigate the oscillating characteristics of vessels and offshore structures in regular wave. The most important problem in this analysis is how to estimate a signal of periodic wave components from the short data disturbed by noise having an unknown basical wave period ; that is, it depends on how to search for the unknown wave period. The authors have approached a solution of this difficult problem by using an index "G_p" described in the following text, which is like a projection ratio of Fourier coefficient powers. This method has been developed in answer to practical demands and used with satisfactory results so far.