| The background of this thesis is the project of "Research of microwave remote sensing on soil moisture" sponsored by National Natural Science Foundation of China, which aims to promote the application of microwave remote sensing in the inspection of soil moisture. Five topics are focused on: the influence of three kinds of priori knowledge hypothesis on soil moisture inversion, the modified BSM in inhomogeneous profile of soil moisture, the coherent part of scattering coefficient and emissivity of BSM, the coherent part of scattering coefficient under measuring conditions, the improvement of soil moisture inversion method.Autocorrelation function of soil surface height, soil temperature and soil texture are three main kinds of priori knowledge hypothesis in microwave remote sensing. Based on BSM, using ANN as inversion tool, the influence of these three hypotheses is gained.The real profile of soil moisture isn't constant, moisture value relates to the depth of soil. BSM is modified to calculate the scattering coefficient and emissivity of soil moisture profile.The formula of coherent part of scattering coefficient and emissivity is gained by Consulting BSM, the value is calculated under the practical measuring conditions: the area and distance of remote sensing object is finite, the incident wave is spherical wave.The precision of soil moisture can be improved by using priori knowledge in the ANN inversion. The method is introduced and the effect is showed in this thesis.
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