Channel modeling and analysis of ULA massive MIMO systems

Abstract

In massive multiple-input multiple-output (MIMO) systems, the favorable propagation which can be also known as the orthogonality of the channel between different users is the most important property. In this paper, we establish a 3-D geometrical channel model for uniform linear array (ULA) massive MIMO systems, and we focus on the orthogonality of the channel, the condition number and the channel capacity. We use the plane wave (PW) to model the far-field signals, and use the spherical wave (SW) to model the near-field signals. Both the azimuth angle of arrival (AAoA) and elevation angle of arrival (EAoA) have been taken into account. Compared with the independent and identically distributed (i.i.d.) Rayleigh fading channels, the proposed channel model comprises the parameters of communication environment and antennas such as environment scattering status, SW effect, antenna spacing etc. The relationship between the performance of massive MIMO systems and parameters is analyzed. The proposed model is easy to be implemented and can be adjusted according to the communication environment.