Transmit Filter and Artificial Noise Design for Secure MIMO-OFDM Systems

TL;DR

This paper proposes novel transmit filtering and artificial noise techniques to enhance physical layer security in MIMO-OFDM systems, effectively disrupting eavesdroppers while preserving legitimate communication quality.

Contribution

It introduces a transmit filter and artificial noise scheme that jointly improve security against multi-antenna eavesdroppers in MIMO-OFDM systems.

Findings

Transmit filter disrupts eavesdropper signals without affecting legitimate reception

Artificial noise further enhances security by disturbing eavesdropper reception

Simulation results confirm improved security performance

Abstract

Physical layer security has been considered as an important security approach in wireless communications to protect legitimate transmission from passive eavesdroppers. This paper investigates the physical layer security of a wireless multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) communication system in the presence of a multiple-antenna eavesdropper. We first propose a transmit-filter-assisted secure MIMO-OFDM system which can destroy the orthogonality of eavesdropper's signals. Our proposed transmit filter can disturb the reception of eavesdropper while maintaining the quality of legitimate transmission. Then, we propose another artificial noise (AN)-assisted secure MIMO-OFDM system to further improve the security of the legitimate transmission. The time-domain AN signal is designed to disturb the reception of eavesdropper while the legitimate transmission will not be affected. Simulation results are presented to demonstrate the security performance of the proposed transmit filter design and AN-assisted scheme in the MIMO-OFDM system.