Enhancing the Physical Layer Security of Dual-functional Radar Communication Systems

TL;DR

This paper proposes a novel fractional programming approach to enhance physical layer security in dual-functional radar-communication systems, effectively safeguarding communication secrecy while maintaining radar performance.

Contribution

It introduces a new optimization framework that accounts for target location uncertainty to improve security in DFRC systems.

Findings

Secrecy rate can be guaranteed under perfect CSI.

Target location uncertainty impacts security performance.

Proposed method effectively balances radar and communication security.

Abstract

Dual-functional radar communication (DFRC) system has recently attracted significant academic attentions as an enabling solution for realizing radar-communication spectrum sharing. During the DFRC transmission, however, the critical information could be leaked to the targets, which might be potential eavesdroppers. Therefore, the physical layer security has to be taken into consideration. In this paper, fractional programming (FP) problems are formulated to minimize the signal-to-interference-plus-noise ratio (SINR) at targets under the constraints for the SINR of legitimate users. By doing so, the secrecy rate of communication can be guaranteed. We first assume that communication CSI and the angle of the target are precisely known. After that, problem is extended to the cases with uncertainty in the target's location, which indicates that the target might appear in a certain angular interval. Finally, numerical results have been provided to validate the effectiveness of the proposed method showing that it is viable to guarantee both radar and secrecy communication performances by using the techniques we propose.