UAV-Aided Jamming for Secure Ground Communication with Unknown Eavesdropper Location

TL;DR

This paper proposes an UAV-assisted jamming strategy to enhance physical layer security in ground communication, effectively maintaining high secrecy rates even when the eavesdropper's exact location is unknown.

Contribution

It introduces an optimization framework for UAV flight path and jamming power to maximize secrecy rate without knowing the eavesdropper's precise position.

Findings

Optimal UAV flight path improves secrecy rate.

Secrecy rate remains high despite unknown eavesdropper location.

UAV jamming stabilizes secrecy rate against eavesdropper power increase.

Abstract

This paper investigates unmanned aerial vehicle (UAV)-aided jamming technique for enabling physical layer keyless security in scenarios where the exact eavesdropper location is unknown. We assume that the unknown eavesdropper location is within an ellipse characterizing the coverage region of the transmitter. By sequentially optimizing the transmit power, the flight path of the UAV and its jamming power, we aim at maximizing the average secrecy rate with arbitrary eavesdropper location. Simulation results demonstrate that the optimal flight path obtains better secrecy rate performance compared to that using direct UAV flight path encasing the transmitter and the legitimate receiver. Most importantly, even with the unknown eavesdropper location, we obtained a secrecy rate that is comparable to a scenario when the eavesdropper's location is known. However, the average secrecy rate with the unknown eavesdropper location varies depending on the proximity of the eavesdropper to the known location of the transmitter. We also observe that due to the UAV-aided jamming, the average secrecy rate stabilizes at some point even though the average received envelope power of the eavesdropper increases. This essentially demonstrates the effectiveness of the proposed scheme.