Space-Time-Frequency Characterization of 3D Non-Isotropic MIMO Multicarrier Propagation Channels Employing Directional Antennas

In this paper we propose a new model for multiple-input multiple-output (MIMO) multicarrier channels in a 3D scattering medium. The proposed model describes the cross-correlation function (CCF) between two sub-channels of an outdoor MIMO channel employing directional antennas in the presence of non-isotropic wave propagation in the 3D space. The derived CCF consists of some correlation terms. Each correlation term is in the form of a linear expansion of averaged Bessel functions of the first kind with different orders. In practice, each correlation term has a limited number of components. Our evaluations of the CCF show the impact of different parameters of the propagation environment and the employed antennas. Our numerical results appear as a good match to the available reported experimental data of some 3D outdoor propagation media.