Application Of The Oceanic Composites' Dielectric Property To The Ocean Remote Sensing

Firstly, A perturbation method is used to study effective response of nonlinearKerr composites. Under the external AC and DC electric field, the effective nonlinearresponses and local potentials are induced by the cubic nonlinearity of Kerr materialsat all harmonics. we have investigated this kind of nonlinear composites withspherical inclusions embedded in a host. At all harmonic frequencies, the potentials ininclusion and host regions are derived. Furthermore, the formulae of the effectivelinear and nonlinear responses are given in the dilute limit. Secondly, The impact ofbreaking waves driven by strong wind on the microwave ocean remote sensing is alsoinvestigated. According to the special property of the foam and water droplets, on thebasic of the effective medium approximation theory of composite, thewhitecap-covered sea surface is treated as a medium layer of dense seawater dropletsand air. On the one hand, The empirical model is remedied to investigate themicrowave emissivity of sea surface under wave breaking. In this model, we havediscussed the effects of spherical bubbles and droplets of whitecaps and difference intemperature between air and sea water (DTBAS) on the emissivity of sea surface. Themodel results indicate that the effective seawater emissivity increases with DTBASincrease. By calculating the effective dielectric constant of witecaps layer, the impactsof bubbles and thickness of whitecaps layer on the seawater emissivity are included inour model. On the other hand, two electromagnetic scattering models of randomlyrough surface are applied to investigate microwave backscattering of breaking waves.The impact of seawater droplets shapes, such as sphere and ellipsoid, and the seawatertemperature to the backscattering coefficient are discussed. Numerical results ofmodels are in good agreement with the experimental measurements and theusableness of models in our paper is proved. Lastly, the impact of rainning to themicrowave remote sensing is discussed.