| Summary: | 碩士 === 國立中正大學 === 地震研究所暨應用地球物理研究所 === 97 === In this paper, we used the EM wave theory [Kong, 1990; Jones, 1994] to construct a two-dimensional multi-layered model to understand the propagation characteristics of EM waves in stratified media. In view of three application domains (Remote Sensing, Coating, and Absorptive materials), we calculate the reflectivity of EM wave that propagate through a multi-layered media then used the results to discuss how the parameters of media and the incident conditions would influence the reflectivity.
According to the results, the increasing of media thickness will cause the periodic repetition of reflectivity curve, and won’t change the maximum value; when the material is magnetic and non-absorptive, the reflectivity will decrease if the permeability is not very large and the incident angle is low. In addition, choosing the appropriate permeability will make the reflectivity independent of the change of the incident angle; the imaginary part of the permittivity and permeability will cause the absorption, furthermore, with equal value of change, the change on permeability will cause more variation on reflectivity than the change on permittivity will do.
The reflection result of one obliquely incident EM wave depends on its polarization: The reflectivity of TE wave will increase with incident angle and that of TM wave will decrease with incident angle. This characteristic will still hold when other parameters of the material are changed.
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