Cooperative Jamming for Wireless Physical Layer Security

TL;DR

This paper proposes a novel multi-antenna relay system design for cooperative jamming in wireless networks, aiming to maximize secrecy rate or minimize power while ensuring security against eavesdroppers.

Contribution

It introduces a new system design with closed-form solutions for antenna weights and power allocation, optimizing physical layer security with nulling constraints.

Findings

Closed-form solutions for antenna weights and power allocation.

Enhanced secrecy rate with multi-antenna relay design.

Effective power minimization under secrecy constraints.

Abstract

Cooperative jamming is an approach that has been recently proposed for improving physical layer based security for wireless networks in the presence of an eavesdropper. While the source transmits its message to its destination, a relay node transmits a jamming signal to create interference at the eavesdropper. In this paper, a scenario in which the relay is equipped with multiple antennas is considered. A novel system design is proposed for determining the antenna weights and transmit power of source and relay, so that the system secrecy rate is maximized subject to a total transmit power constraint, or, the transmit power is minimized subject to a secrecy rate constraint. Since the optimal solutions to these problems are difficult to obtain, suboptimal closed-form solutions are proposed that introduce an additional constraint, i.e., the complete nulling of jamming signal at the destination.