Optimization of MIMO STEEP for Secure Communications over MIMOME Channels

2026-07-22

AI Summary

This work addresses the challenge of achieving positive secrecy rates in MIMOME (multiple-input multiple-output multiple-eavesdropper) wiretap channels where the eavesdropper’s channel is stronger than that of the legitimate receiver—a scenario in which conventional schemes typically fail. Focusing on a system with multi-antenna legitimate users and a multi-antenna eavesdropper, the paper proposes an optimized precoder design based on the STEEP transmission framework. It is the first to demonstrate that carefully crafted precoding can substantially enhance the achievable secrecy rate of MIMO STEEP. Experimental results confirm that the proposed approach yields significant gains in positive secrecy rates even under strong eavesdropping conditions, offering a promising new direction for high-security wireless communication systems.

Abstract

A transmission scheme for secure communications, called secret-message transmission by echoing encrypted probes (STEEP), can deliver a positive secrecy rate, even when eavesdropping channels are much stronger than that between users, subject to sufficient asymmetric power allocations from users. This paper considers an optimization problem for STEEP applied to MIMO (or MIMOME) channels between multi-antenna users and multi-antenna Eve. We reveal for the first time a significant increase of the achievable secrecy rate of MIMO STEEP using optimized precoders.

Problem

• MIMO
• STEEP
• secure communications
• secrecy rate
• MIMOME

Innovation

• MIMO STEEP
• secrecy rate optimization
• precoder design
• MIMOME channels
• secure communications