Outage Probability Minimization for UAV-Enabled Data Collection with Distributed Beamforming

TL;DR

This paper proposes a joint optimization of UAV trajectory and sensor power to minimize outage probability in UAV-enabled data collection, using convex optimization techniques, with significant performance improvements demonstrated.

Contribution

It introduces a novel joint optimization framework for UAV trajectory and sensor power allocation to minimize outage probability, including solutions for ideal and constrained flight scenarios.

Findings

Proposed algorithm reduces outage probability significantly.

Optimal solution in ideal case reveals fundamental performance bounds.

Numerical results outperform benchmark schemes.

Abstract

This paper studies an unmanned aerial vehicle (UAV)-enabled wireless sensor network, in which one UAV flies in the sky to collect the data transmitted from a set of sensors via distributed beamforming. We consider the delay-sensitive application scenario, in which the sensors transmit the common/shared messages by using fixed data rates and adaptive transmit powers. Under this setup, we jointly optimize the UAV's trajectory design and the sensors' transmit power allocation, in order to minimize the transmission outage probability, subject to the UAV's flight speed constraints and the sensors' individual average power constraints. However, the formulated outage probability minimization problem is non-convex and thus difficult to be optimally solved in general. To tackle this issue, we first consider the special problem in the ideal case with the UAV's flight speed constraints ignored, for which the well-structured optimal solution is obtained to reveal the fundamental performance upper bound. Next, for the general problem with the UAV's flight speed constraints considered, we propose an efficient algorithm to solve it sub-optimally by using the techniques of convex optimization and approximation. Finally, numerical results show that our proposed design achieves significantly reduced outage probability than other benchmark schemes.