Radar sensing of ocean wave heights

Abstract

This thesis focuses on explaining and improving the estimation of ocean wave heights from high-frequency oceanographic radar. Three months of data from a WERA HF radar is compared to a Datawell MarkIII directional waverider buoy, under a wide range of sea states. Large spatial and temporal variation in the radar-derived waveheight, significantly greater than previously reported, are explained in terms of various error sources. Averaging and filtering methods for improving the significant waveheight are evaluated, and the dominant error source is shown to be external radio frequency interference. Eigen-analysis and model-based methods are evaluated for the removal of interference. A comprehensive summary of the second order radar-ocean scattering equations is given, with evaluation of its terms.