On the Second Order Statistics of Cooperative UAV Communications underlying Interference Limited Composite Fading Conditions

Abstract

Unmanned-aerial-vehicles (UAVs) enabled communications (ECs) are intended to be an essential part of forthcoming beyond 5G (B5G) and 6G communication networks (CNs). UAV-to-ground (UG)-ECs in densely populated areas are usually exposed to composite fading conditions and the impact of co-channel interference (CCI). In this paper, we provide second order (SO)-metrics of UG communications over double-scattered, single-shadowed (DSc-SSh) fading channels in the interference limited environment, modeled as a ratio of the product of double a-µ and Gamma (G) random variables (RVs). Novel integral form formulas for average fade duration (AFD) and level crossing rate (LCR) of the proposed UG communication system over the composite channels in the presence of CCI are efficiently obtained and approximated by Laplace based integration (LBI)-method. Moreover, the system model is extended to investigate the SO-metrics of cooperative UAV transmission selection (TS) system that chooses the UG transmission link with the highest signal level among L independent UG links. The impact of different DSc-SSh fading conditions as well as the number of UAVs on the SO- metrics are well addressed.