Enhancing Network Capacity With Transmission Range Optimization in UAV Ad Hoc Networks

In UAV ad hoc networks (UANETs), transmission range of transmitters is a crucial factor in ensuring network capacity. Inadequate adjustment of transmission range may lead to link disconnection or excessive interference when network topology changes, worsening network capacity. In this paper, we study the impact of transmission range on network capacity characterized by spatial throughput (ST) in UANETs under external jamming and design a power control strategy to achieve optimal transmission range (OTR). Specifically, transmitters and jammers are modeled by a three-dimensional Poisson cluster process and a three-dimensional Poisson point process, respectively. Analysis of ST is accordingly given to illustrate the impact of topology changes and jamming. Afterwards, we analyze ST under transmission range and find that ST scales with the transmission range R as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$e^{\kappa _{1}R^{3}}\left ({{1-e^{\kappa _{2}R^{3}}}}\right),\left ({{\kappa _{1},\kappa _{2}\lt 0}}\right)$ </tex-math></inline-formula>. This indicates that ST first increases and then decreases with the transmission range. In other words, an OTR exists, which maximizes ST, and it is proved that the OTR scales with node density <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda $ </tex-math></inline-formula> as <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Theta {\left ({{\lambda ^{-\frac {1}{3}}}}\right)}$ </tex-math></inline-formula>. Accordingly, we propose a power control strategy implemented at each transmitter to achieve OTR and enhance ST. Simulation results show that ST adopting OTR linearly increases with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda $ </tex-math></inline-formula>, and the proposed strategy shows superiority in enhancing ST under intense jamming among other strategies.