Dielectric properties of ice crystals at microwave frequency range

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The aim of this project is to measure the dielectric constant and dielectric permittivity of single and poly crystals of ice and those which are doped acid (HNO_3, H_2SO_4 and HCl) and salt (NaCl). The range of microwave is from 100MHz to 40GHz. The dielectric measurement of ice under microwave region is so hard that the reliable result has not been reported even though the value of dielectric constant and permittivity is used to be analyzed the signal of satellite-born SAR.and microwave remote sensing in cold and polar regions.The results which we obtained are as follows.(1) anisotropy of dielectric constantThe precise measurement of dielectric constant shows the anisotropy of the constant is 0.327 over the frequency range of the measurement.(2) permittivity and conductivity of doped icePermittivity and conductivity of acid-doped ice at microwave frequency region linearly depend on the concentration of H^+ ion (molar concentration). Those of NaCl-doped ice also depend on the concentration of NaCl.(3) dielectric constant and permittivity of snowBased on the results of (1) and (2), the scattering model of microwave in snow is established and the density and grain size dependence of the dielectric constant and permittivity of snow is explained by the simulation of the model. These results are consistent to the results of the measurements.