Power-Efficient Deployment of UAVs as Relays

TL;DR

This paper investigates the optimal deployment and selection strategies for UAVs acting as communication relays to minimize power consumption in fixed-rate systems, analyzing centralized and distributed approaches with theoretical and numerical methods.

Contribution

It introduces a comprehensive analysis of UAV relay deployment considering both centralized and distributed selection scenarios, using quantization theory to derive optimal power tradeoffs.

Findings

Optimal UAV deployment strategies depend on the number of UAVs and their locations.

Theoretical analysis confirms the power tradeoffs in extremal regimes.

Numerical results validate the analytical models and optimization approaches.

Abstract

Optimal deployment of unmanned aerial vehicles (UAVs) as communication relays is studied for fixed-rate variable-power systems. The considered setup is a set of ground transmitters (GTs) wishing to communicate with a set of ground receivers (GRs) through the UAVs. Each GT-GR pair communicates through only one selected UAV and have no direct link. Two different UAV selection scenarios are studied: In centralized selection, a decision center assigns an optimal UAV depending on the locations of all terminals. In distributed selection, a GT selects its relaying UAV using only the local knowledge of its distances to the UAVs. For both selection scenarios, the optimal tradeoff between the UAV and GT power consumptions are determined using tools from quantization theory. Specifically, the two extremal regimes of one UAV and very large number of UAVs are analyzed for a path loss exponent of $2$. Numerical optimization of UAV locations are also discussed. Simulations are provided to confirm the analytical findings.