Safeguarding Wireless UAV Communications

Overview

This PhD research develops physical-layer security frameworks for UAV-assisted wireless networks, with trajectory design as the central optimization lever. By treating the UAV’s mobility as a controllable degree of freedom — jointly optimized with beamforming, power allocation, and jamming — the work demonstrates that aerial platforms can achieve security gains that are structurally inaccessible to fixed infrastructure.

The program spans four interconnected thrusts. The first establishes baseline security and energy performance for UAV-enabled AF relaying under cooperative jamming and simultaneous wireless information and power transfer (SWIPT), deriving closed-form benchmarks under Rician fading. The second develops joint trajectory and resource optimization frameworks — using successive convex approximation (SCA) and robust design under channel uncertainty — for artificial-noise-aided UAV transmitters facing passive eavesdroppers. The third introduces deep reinforcement learning (DRL) for full-duplex MIMO-UAV relaying against active eavesdroppers, where the adversary’s CSI is unavailable and the state space is too complex for model-based methods. The fourth extends the architecture to emerging physical-layer paradigms: terahertz (THz) bands with untrusted UAV relays (minimizing secrecy energy efficiency via co-designed trajectory and communication), and aerial intelligent reflecting surfaces (IRS) enabling covert THz communications in B5G IoT deployments.

Technical Contributions

1. Milad Tatar Mamaghani, ``Safeguarding Beyond-5G Wireless Communications with Unmanned Aerial Vehicles: Design and Optimization,” Ph.D. Thesis, Electrical and Computer Systems Engineering Department, Faculty of Engineering, Monash University, Melbourne, Australia, Dec. 2022.

2. Milad Tatar Mamaghani and Yi Hong, “Aerial Intelligent Reflecting Surface-Enabled Terahertz Covert Communications in Beyond-5G Internet of Things,” IEEE Internet of Things Journal, vol. 9, no. 19, pp. 19012–19033, Oct. 2022.

3. Milad Tatar Mamaghani and Yi Hong, “Terahertz Meets Untrusted UAV-Relaying: Minimum Secrecy Energy Efficiency Maximization via Trajectory and Communication Co-Design,” IEEE Transactions on Vehicular Technology, vol. 71, no. 5, pp. 4991–5006, May 2022.

4. Milad Tatar Mamaghani and Yi Hong, “Intelligent Trajectory Design for Secure Full-Duplex MIMO-UAV Relaying Against Active Eavesdroppers: A Model-Free Reinforcement Learning Approach,” IEEE Access, vol. 9, pp. 4447–4465, Dec. 2021.

5. Milad Tatar Mamaghani and Yi Hong, “Joint Trajectory and Power Allocation Design for Secure Artificial Noise Aided UAV Communications,” IEEE Transactions on Vehicular Technology, vol. 70, no. 3, pp. 2850–2855, Mar. 2021.

6. Milad Tatar Mamaghani and Yi Hong, “Improving PHY-Security of UAV-Enabled Transmission With Wireless Energy Harvesting: Robust Trajectory Design and Communications Resource Allocation,” IEEE Transactions on Vehicular Technology, vol. 69, no. 8, pp. 8586–8600, Aug. 2020.

7. Milad Tatar Mamaghani and Yi Hong, “On the Performance of Low-Altitude UAV-Enabled Secure AF Relaying With Cooperative Jamming and SWIPT,” IEEE Access, vol. 7, pp. 153060–153073, Oct. 2019.