Nonstationary Wave Field Analysis using new Harmonic Phase Tracking Technique

摘要

This paper introduces a new signal processing technique called Harmonic Phase Tracking (HPT), and uses it to investigate physically-meaningful properties of random seas. The fundamental improvement over FFTs is that HPT adaptively solves for the rank and best component frequencies along with amplitudes and phases. HPT can be applied to wideband ocean waves to recover time-varying information associated with nonstationary conditions. Analyses suggest that random seas are in fact "quasi-deterministic", with wave packets at discrete frequencies, with continuity for long periods of time (e.g., one hour) and large spatial extents (several wavelengths).