  In this paper, a novel three-dimensional (3D) non-stationary geometry-based
stochastic model (GBSM) for the fifth generation (5G) and beyond 5G (B5G)
systems is proposed. The proposed B5G channel model (B5GCM) is designed to
capture various channel characteristics in (B)5G systems such as
space-time-frequency (STF) non-stationarity, spherical wavefront (SWF), high
delay resolution, time-variant velocities and directions of motion of the
transmitter, receiver, and scatterers, spatial consistency, etc. By combining
different channel properties into a general channel model framework, the
proposed B5GCM is able to be applied to multiple frequency bands and multiple
scenarios, including massive multiple-input multiple-output (MIMO),
vehicle-to-vehicle (V2V), high-speed train (HST), and millimeter wave-terahertz
(mmWave-THz) communication scenarios. Key statistics of the proposed B5GCM are
obtained and compared with those of standard 5G channel models and
corresponding measurement data, showing the generalization and usefulness of
the proposed model.
