The Study On Inversion Of Ocean Wave Spectrum For Ocean Wave Spectrometer

The ocean wave spectrometer is real aperture radar to measure directional spectra ofwaves. Through looking at angles near the vertical and scanning over360°in azimuth, Thisinstrument can provide global long time observation of the normalized radar cross section.The wave directional spectra, the significant wave height and wind speed is inversed from thenormalized radar cross section observed by ocean wave spectrometer. This thesis focuses onthe ocean wave remote sensing theory, the simulation of the Space-borne spectrometer andresearches on inversing method to improve the retrieval accuracy of ocean wave spectrum.Firstly, the principle of ocean wave spectrometer is analyzed to measure wave spectrum.At small incidence, quasi-mirror reflection is its scattering mechanism and the tilt modulationof long wave is its detection mechanism. The linear relation between echo power spectrumand wave-slope spectrum is built based on the two points. Secondly, the step and qualityindex of the simulation of the Space-borne spectrometer is introduced in detail. Finally, threeimproved methods are carried out to improve the retrieval accuracy of ocean wave spectrum,which are consideration of non-Gaussian sea surface, estimation method of tilt modulationfunction and optimization of spectrum estimation algorithm.The results of simulation show that ocean wave spectrometer can measure ocean wavespectrum accurately. The relevancy between inverting modulation spectrum and referencemodulation spectrum is all enhanced by improved methods, and the errors are reduced.