mmWavePropagation Modelling: Atmospheric Gaseous and Rain Losses

This chapter summarizes contemporary wave propagation models developed by AT&T and modified by researchers at Stanford University. The pioneering work by Van Vlec contributed to a better insight of the basic characteristics millimetre Waves absorption by molecular of atmospheric gases. Atmospheric gaseous specific attenuation can be calculated by two related methods: the computation-intensive line-by-line calculation and the computationally less-intensive procedure. The chapter explains signal attenuation by atmospheric gases and the corresponding International Telecommunication Union recommendations. It describes the rain attenuation at mmWave frequency bands for horizontal and vertical linear and circular polarizations. The physical rain Capsoni model was developed by C. Capsoni et al. for predicting the rain degradation of radio wave propagation. The chapter presents the attenuation by snow and hail and electromagnetic propagation transmission models, together with an introduction to the strong fluctuation theory. It provides the snow dielectric properties using the strong fluctuation theory.