粗糙地、海面色散特性研究

由于在研究粗糙地海面的超宽带特性时,需记及介电常数随频率变化而变化的特点.因此,有必要研究粗糙地海面中随机介质的介电常数随频率变化的色散特性.通过自由水和结合水色散特性的数值比较,提出了一种包含结合水的新土壤介电常数模型,研究了新旧模型随频率变化的特性,结果表明新的土壤模型比Dobson模型更合理地表征了土壤的介电常数.同时,针对海水的色散特性,通过单、双Debye模型的数值对比,提出了修正的Meissner模型,研究了海水在不同温度下的色散特性,分析了不同温度下的松弛频率,结果表明第2个松弛频率的引入显著拓展了Debye模型的有效范围,从而证明了新模型的有效性.

Study of the Dispersion of Rough Land and Sea Surface

On account of the changing of permittivity along with frequency, it is necessary that the dispersion of rough land and sea surface should be studied. Based on the study of dispersion of land surface, a novel model including the bound water is presented by comparing the dispersion of bound water with that of free water. The relationship between permittivity and frequency is studied, and the result shows that the model is more preferable than the Dobson''s. On the other hand, a modified model for the permittivity of sea surface is presented by comparing the single and double Debye models in relaxation law. The dispersion of sea surface is studied, and the relaxation frequencies are analyzed at different temperature respectively. The results show that it is the second relaxation frequency that obviously expands the effective range of Debye model, which confirms the validity of the new model.