Time Non-stationary RS-GBSM for UAV Wideband Channels

In this chapter, we propose a three-dimensional (3D) geometry-based stochastic model (GBSM) for multiple-input multiple-output (MIMO) wideband time non-stationary channels between the unmanned aerial vehicle (UAV) and the ground user. The proposed model uses a single concentric-cylinders model, where the signal is a superposition of a line-of-sight (LoS) component and single-bounced (SB) rays. In order to describe time non-stationarity of the channel, time-varying angles have been properly derived and added in the proposed model. At the same time, based on the reference model, we derive the expressions of the channel statistical properties of the space–time–frequency correlation function (STF-CF) and space-Doppler power spectral density (SD-PSD). In addition, the corresponding deterministic and stochastic simulation models are developed based on the reference model. Moreover, we investigate the influence of some important UAV-related parameters on channel statistical properties as well as the time non-stationarity. Some interesting observations and conclusions are obtained, which are helpful for the design of UAV communication systems. Finally, the great agreement between simulation models and the reference model demonstrates not only the utility of simulation models but also the correctness of theoretical derivations and simulations.