Causes of phase variations in the air–ice boundary reflection coefficient in the microwave range

Abstract

538.566We study phase variations in the coefficient of reflection from a flat air-ice boundary at the ice melting point. The measurements were performed by different methods at frequencies 3.3, 6, 13, and 32 GHz. The experimental data were compared with simple theoretical models. It was found that ice wettening in thin layers leads to a phase variation in the reflection coefficient by up to a few ten degrees with satisfactory agreement between the experiment and the theory. However, anomalies of the transmission properties of the samples unexplainable in terms of the model of effective dielectric permittivity of the melting layers were observed in a narrow temperature range before the ice destruction.