On the Second Order Statistics of 3D Non-Stationary UAV Channels Allowing Velocity Variations

The level crossing rate and average fading duration are two important statistical properties of channel fading envelope. In this paper, a geometry-based stochastic model for unmanned aerial vehicle (UAV) channel allowing three-dimensional trajectory of the UAV and ground station is proposed. On this basis, the theoretical expressions of level crossing rate and average fading duration are analyzed and derived. Under the UAV high-speed flight scenarios, numerical simulations show that the theoretical results of level crossing rate and average fading time agree well with the simulated and measured ones. The proposed model and derived expressions are very helpful for the design of block interleave and channel coding in UAV communication systems.