A Novel 3-D Massive MIMO Channel Model for Vehicle-to-Vehicle Communication Environments

This paper presents 3-D vehicle massive multiple-input multiple-output (MIMO) antenna array model for vehicle-to-vehicle (V2V) communication environments. A spherical wavefront is assumed in the proposed model instead of the plane wavefront assumption used in the conventional MIMO channel model. Using the proposed V2V channel model, we first derive the closed-form expressions for the joint and marginal probability density functions of the angle of departure at the transmitter and angle of arrival at the receiver in the azimuth and elevation planes. We additionally analyze the time and frequency cross-correlation functions for different propagation paths. In the proposed model, we derive the expression of the Doppler spectrum due to the relative motion between the mobile transmitter and mobile receiver. The results show that the proposed 3-D channel model is in close agreement with previously reported results, thereby validating the generalization of the proposed model.

I. Introduction

Multiple-input multiple-output (MIMO) technologies have received considerable attention for modern wireless communication systems because they can substantially increase spectral efficiency [1], [2]. Recently, massive MIMO systems, which are equipped with hundreds or even thousands of antennas, have emerged as enhanced MIMO systems to meet the increasing traffic demands of fifth-generation (5G) wireless communication networks [3]. In general, massive MIMO has been regarded as an efficient means of improving both spectrum efficiency and energy efficiency for wireless communication systems. They are thus significantly better than the conventional MIMO systems [4]. More specifically, it has been suggested that massive MIMO vehicle-to-vehicle (V2V) communication environments comprise a promising technology for 5G wireless communication networks. To create the above communication systems, a solid understanding of the radio propagation characteristics of the transmission paths between the mobile transmitter and mobile receiver is required [5]. This understanding can result in the design of effective signal processing techniques. Additionally, Wood and Hodgkiss [6] demonstrated that correlation-based conventional MIMO channel models, such as the respective Kronecker and Weichselberger models, can be used to analyze the performance of compact MIMO systems.