Waveform Design for Secure SISO Transmissions and Multicasting

TL;DR

This paper introduces a novel waveform design method for secure SISO wireless transmissions and multicasting, optimizing for eavesdropper interference and receiver SINR under various knowledge scenarios, validated through extensive simulations.

Contribution

It proposes new waveform design strategies for physical-layer security in SISO systems, including methods for when eavesdropper CSI is known or unknown, and extends to multicasting scenarios.

Findings

Waveform design reduces eavesdropper SINR effectively.

Artificial noise enhances security when eavesdropper CSI is unknown.

Simulation results confirm improved security performance.

Abstract

Wireless physical-layer security is an emerging field of research aiming at preventing eavesdropping in an open wireless medium. In this paper, we propose a novel waveform design approach to minimize the likelihood that a message transmitted between trusted single-antenna nodes is intercepted by an eavesdropper. In particular, with knowledge first of the eavesdropper's channel state information (CSI), we find the optimum waveform and transmit energy that minimize the signal-to-interference-plus-noise ratio (SINR) at the output of the eavesdropper's maximum-SINR linear filter, while at the same time provide the intended receiver with a required pre-specified SINR at the output of its own max-SINR filter. Next, if prior knowledge of the eavesdropper's CSI is unavailable, we design a waveform that maximizes the amount of energy available for generating disturbance to eavesdroppers, termed artificial noise (AN), while the SINR of the intended receiver is maintained at the pre-specified level. The extensions of the secure waveform design problem to multiple intended receivers are also investigated and semidefinite relaxation (SDR) -an approximation technique based on convex optimization- is utilized to solve the arising NP-hard design problems. Extensive simulation studies confirm our analytical performance predictions and illustrate the benefits of the designed waveforms on securing single-input single-output (SISO) transmissions and multicasting.