| Passive microwave remote sensing of ocean surface is an intercross subject with oceanography and electromagnetic dynamics, which is extremely useful for marine and environment monitoring. This thesis focuses on remote sensing of SSS (sea surface salinity), SST (sea surface temperature) and wind vector by using microwave radiometer. Based on theories on ocean waves and E-M radiation, a few previous models on microwave remote sensing are improved and some new algorithms for retrieving SSS and SST are proposed. Thus, this study would make important contribution to our country for monitoring ocean and microwave remote sensing. Ocean surface emissivity is a key for study on microwave remote sensing.However, emissivity is a complicated function related to a few parameters, such as the sea surface temperature, sea surface salinity and sea surface roughness induced by wind. Reducing number of the unknown parameters in a single model is an effective way to improve technology in microwave remote sensing and develop new algorithms for retrieving the sea surface parameters.Two-scale model and Small-Slope-Approximation model are two popular models for computing the emissivity. In this study, the advantages and disadvantages of these two models are analyzed, and the effects of parameters in the models, such as ocean wave spectrums and permittivity, on the retrieved errors are investigated in detail. It is validated that a new method proposed in this study based on the two-scale model, is more accurate than the original one by comparing with the Windrad05, an empirical model.According to electromagnetic radiation and transfer theory, an algorithm used for the fully-polarimetric microwave radiometer to retrieve ocean wind vector, SST, vapor and liquid is built based the two-scale model. The data measured by WindSat, which is the world's first fully-polarimetric microwave radiometer in space, is used as the input of the algorithm, and the wind direction ambiguity and retrieved oceanic wind error are focused on. It is preliminarily validated that ocean surface wind vectors can be well detected by a fully-polarimetric microwave radiometer from space.The retrieved selection due to the ambiguities between upwind/downwind may cause 180°error of wind direction, which is a unacceptable error. The harmonic expansions for the four Stokes brightness temperature components are investigated. Local minima of the cost function, other than the global minimum, correspond to erroneous solutions that could cause an ambiguous case in the presence of noise. The values of the Stokes components T3 and T4 are small and the signs are much alike with azimuth angle in the range of 0-30°and 180-200°, as well as azimuth angle in the range of 150-180°and 330-360°. In the presence of noise, the azimuth angles in the range of 0-30°(150-180°) may be retrieved into the range of 180-210°(330-360°). Based on Monte Carlo simulation, an algorithm is proposed to obtain wind direction according to first and second rank solutions of the first scan and first rank solution of the second scan. The new algorithm can avoid upwind/downwind ambiguous solution.Remote sensing of sea surface salinity (SSS) depends on the microwave radiation of sea water at 1.4GHz, and also on the sea surface wind that affects the microwave radiation. The properties of emission at L-band (1.4GHz) of calm sea surface and seawater permittivity are investigated. There are obvious differences between two different seawater permittivity algorithms, which will influence on the retrieval of SSS. Since the stabilization is a big problem for airplane and the error of retrieved SSS caused by uncertainty of incidence angle is less with smaller incidence angle, designing a small incidence angle can give us benefit to improve the precision of SSS retrieval from aerial survey.The effects of sea surface wind on sea surface brightness temperature, i.e. ?Th,v, and the relations among ?Th,v, wind speed, sea surface temperature, sea surface salinity and incidence angle of observation are investigated. A new formula about (?Th+?Tv) is proposed. This formula could be considered as the foundation of statistical model for SSS retrieve. A new algorithm depending on the design of a single radiometer with double polarizations and multi-incidence angles is proposed. The algorithm excludes the influence of sea surface wind on SSS and SST retrieval, and provides a new method for remote sensing of SSS and SST.
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