Security of Rechargeable Energy-Harvesting Transmitters in Wireless Networks

TL;DR

This paper studies the security of energy-harvesting wireless transmitters with limited battery capacity, proposing an optimized transmission scheme and beamforming technique to maximize secrecy rates against eavesdroppers.

Contribution

It introduces an energy-aware secrecy enhancement scheme using optimized transmission times and multi-antenna beamforming for rechargeable energy-harvesting nodes.

Findings

Significant secrecy rate improvements with the proposed scheme

Energy arrival rates impact achievable secrecy rates

Beamforming effectively cancels artificial noise at legitimate receiver

Abstract

In this letter, we investigate the security of a single-antenna rechargeable source node in the presence of a multi-antenna rechargeable cooperative jammer and a potential single-antenna eavesdropper. The batteries at the legitimate transmitting nodes (i.e. the source node and the jamming node) are assumed to be limited in capacity and are modeled as queueing systems. We investigate the impact of the energy arrival rates at the batteries on the achievable secrecy rates. In our energy-constrained network, we propose an efficient scheme to enhance the system's security by optimizing the transmission times of the source node. The jammer uses a subset of its antennas (and transmit radio-frequency chains) to create a beamformer which maximizes the system's secrecy rate while completely canceling the artificial noise at the legitimate destination. Our numerical results demonstrate the significant average secrecy rate gain of our proposed scheme.