Joint Location, Bandwidth and Power Optimization for THz-enabled UAV Communications

TL;DR

This paper proposes a joint optimization framework for UAV deployment, power, and bandwidth allocation in THz-enabled UAV communications to minimize transmission delays, addressing the challenges of uncertain THz channels.

Contribution

It introduces a novel joint optimization approach for UAV location, power, and bandwidth in THz systems, with an alternating algorithm to reduce delays significantly.

Findings

Delay reduction up to 59.3%, 49.8%, and 75.5% compared to baseline methods.

Effective joint optimization improves communication efficiency in THz UAV systems.

Proposes an iterative algorithm for nonconvex delay minimization.

Abstract

In this paper, the problem of unmanned aerial vehicle (UAV) deployment, power allocation, and bandwidth allocation is investigated for a UAV-assisted wireless system operating at terahertz (THz) frequencies. In the studied model, one UAV can service ground users using the THz frequency band. However, the highly uncertain THz channel will introduce new challenges to the UAV location, user power, and bandwidth allocation optimization problems. Therefore, it is necessary to design a novel framework to deploy UAVs in the THz wireless systems. This problem is formally posed as an optimization problem whose goal is to minimize the total delays of the uplink and downlink transmissions between the UAV and the ground users by jointly optimizing the deployment of the UAV, the transmit power and the bandwidth of each user. The communication delay is crucial for emergency communications. To tackle this nonconvex delay minimization problem, an alternating algorithm is proposed while iteratively solving three subproblems: location optimization subproblem, power control subproblem, and bandwidth allocation subproblem. Simulation results show that the proposed algorithm can reduce the transmission delay by up to $59.3\%$, $49.8\%$ and $75.5\%$ respectively compared to baseline algorithms that optimize only UAV location, bandwidth allocation or transmit power control.