ABSTRACT In recent years, low‐altitude unmanned aerial vehicles (UAVs) have attracted more and more attention across various fields. Accurate channel modelling is critical for the design and performance evaluation of low‐altitude UAV communication systems, making it an emerging research hotspot. This paper presents a three‐dimensional (3D) wideband non‐stationary Geometry‐Based Stochastic Channel Model (GBSM) for low‐altitude UAV communications. Distinct from existing modelling frameworks, the proposed model integrates air‐to‐air (A2A) and air‐to‐ground (A2G) scenarios into a generalised channel model. Moreover, a two‐state continuous‐time Markov process is employed to characterise the dynamic behaviours of scattering cluster birth and death. And key statistical properties, including space‐time‐frequency correlation and Doppler power spectral density (DPSD), are derived to quantify the channel model. To address computational complexity challenges, a corresponding simulation model is further developed. Simulation results verify that the proposed model effectively captures the channel behaviours of low‐altitude UAV communication systems.
Li et al. (Thu,) studied this question.