Ocean Wave Spectral Estimation Using Vessel Wave Frequency Motions

Parametric and non-parametric spectral descriptions are used to estimate the wave spectra from wave frequency motions of a vessel at low advance speed, using minimization procedures based on a constrained gradient search and a genetic algorithm. The parametric description provides smooth power spectral energies as a result of the analytic spectral description. The non-parametric requires a smoothing post processing if very good readability is needed. It has been concluded that the non-parametric description is faster, more robust to model errors and likely to be a better formulation for adaptive algorithms.