Trajectory Optimization for Multiple UAVs Acting as Wireless Relays


This paper proposes a novel wireless relay selection scheme involving multiple mobile Unmanned Aerial Vehicles (UAVs) to support communicating ground users. The goal is to optimize the transmit power levels and trajectories of the relaying UAVs in order to maximize the data rate transmission of the ground users which are suffering from the absence of direct link. Assuming that each UAV is initially characterized by a predefined trajectory for a primary task, we propose to modify it whenever it is needed and the energy and trajectory boundaries constraints allow. We propose to solve this problem using an iterative two steps solution; first, a Mixed Integer Linear Programming (MILP) problem is formulated to optimally determine the users- UAVs associations and the UAVs' corresponding transmit power levels. In the second step, an efficient algorithm based on a recursive shrink-and-realign process is proposed to optimize the UAV trajectories. The performance of the proposed method shows advantages in terms of average throughput compared to the predefined trajectories solution.

Meeting Name

2018 IEEE International Conference on Communications, ICC 2018 (2018: May 20-24, Kansas City, MO)


Electrical and Computer Engineering

Keywords and Phrases

Iterative methods; Mobile antennas; Trajectories; Unmanned aerial vehicles (UAV), Average throughput; Data rate transmission; Mixed integer linear programming (MILP); Mobile unmanned aerial vehicles; Multiple UAVs; Trajectory optimization; Transmit power; Wireless relays, Integer programming

International Standard Book Number (ISBN)


International Standard Serial Number (ISSN)


Document Type

Article - Conference proceedings

Document Version


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© 2018 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 May 2018