Performance ofWireless Communications using Unmanned Aerial Vehicles
Abstract
The unprecedented recent advances in drone technology has made it possible to widely deploy unmanned aerial vehicles (UAVs) for various wireless communication purposes in military environments One particular use case. However, in order to effectively reap the benefits of using UAVs for communication purposes, it is imperative to meet a number of fundamental challenges that range from the analysis of the communication performance of UAV-equipped access points, to the design of new resource management solutions for optimizing communication performance using UAVs. In this project, we have developed a number of analytical framework that address the aforementioned challenges and shed light on the achievable wireless communication performance by UAVs. First, we have developed a novel framework for deploying and operating a UAV-based antenna array system that can provide connectivity to ground networks via beamforming. Using tools from communication, optimization, and control theory, we have characterized the optimal positioning of the UAV antenna array, that minimizes the time it needs to service ground users. Simulation results have shown that, in comparison with a fixed-array case, the networkÕs spectral efficiency can be improved by 32% while leveraging the proposed UAV antenna array system. Second, we have introduced a novel concept of three-dimensional (3D) wireless networks, that integrate UAV access points (UAV-APs) and wireless-connected UAV users (UAV-UEs). We have then analyzed the performance, in terms of latency, of this new 3D wireless network architecture and proposed various approach to optimize deployment and cell association so as to guarantee minimum latency for UAV-UEs. Simulation results have then shown that the proposed approach yields a reduction of up to 46% in the average latency compared to conventional techniques such as SINR-based association. Third, we have investigated how high altitude platform (HAP) UAVs can provide pervasive wireless connectivity to ground users in remote military areas by establishing line-of-sight links and exploiting effective beamforming techniques. In this context, by exploiting an interference alignment technique, we have developed a novel method for achieving the maximum sum-rate in HAP-based communications without channel state information. The derived theoretical results were then corroborated via extensive simulations. Finally, we have turned our attention to problems of performance analysis and resource management for UAVs that require connectivity to operate in a military environment. Examples include UAVs that gather surveillance data and that need to transmit this data via wireless links to ground access points. In this scenario, we have developed an interference-aware path planning scheme that enables UAVs to find the optimal trajectory that minimizes not only their mission time but also their transmission delay and the interference they cause on ground networks. We have then developed a learning scheme that allows each UAV to dynamically find its optimal path, transmission power level, and cell association vector with ground access points at different locations along its path. Simulation results have shown that the proposed approach achieves better wireless latency per UAV and rate per ground user while requiring a number of steps that is comparable to a heuristic baseline that considers moving via the shortest distance towards the corresponding destinations. In a nutshell, this project has led to new, foundational results on the anticipated performance from networks of UAV that are wireless connected. These results will hence expedite the deployment of connected UAVs in tomorrow s battlefields and military systems.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 22, 2018
- Source ID
- W911NF1710593
Entities
People
- Walid Saad
Organizations
- Army Contracting Command
- United States Army
- Virginia Tech