Location-Based Beamforming for Rician Wiretap Channels

TL;DR

This paper introduces a location-based beamforming method for Rician wiretap channels that enhances physical layer security by utilizing only the eavesdropper's location information, demonstrating robustness against location uncertainties.

Contribution

It develops a beamforming scheme based solely on eavesdropper location to minimize secrecy outage probability in Rician fading environments, with analytical expressions and robustness analysis.

Findings

Beamforming vector depends on eavesdropper's location.

Analytical expression for secrecy outage probability derived.

Method remains effective under location uncertainty.

Abstract

We propose a location-based beamforming scheme for wiretap channels, where a source communicates with a legitimate receiver in the presence of an eavesdropper. We assume that the source and the eavesdropper are equipped with multiple antennas, while the legitimate receiver is equipped with a single antenna. We also assume that all channels are in a Rician fading environment, the channel state information from the legitimate receiver is perfectly known at the source, and that the only information on the eavesdropper available at the source is her location. We first describe how the beamforming vector that minimizes the secrecy outage probability of the system is obtained, illustrating its dependence on the eavesdropper's location. We then derive an easy-to-compute expression for the secrecy outage probability when our proposed location-based beamforming is adopted. Finally, we investigate the impact location uncertainty has on the secrecy outage probability, showing how our proposed solution can still allow for secrecy even when the source has limited information on the eavesdropper's location.