Optimal Power Allocation for A Massive MIMO Relay Aided Secure Communication

TL;DR

This paper investigates optimal power allocation strategies at a massive MIMO relay to enhance security in two-hop wireless communications, providing analytical solutions and validating them through simulations.

Contribution

It introduces a novel analysis and closed-form solutions for optimal relay power allocation in M-MIMO secure communications, addressing practical conditions.

Findings

Closed-form expressions for optimal relay power

Conditions for nonnegative secrecy outage capacity

Asymptotic secrecy performance characteristics

Abstract

In this paper, we address the problem of optimal power allocation at the relay in two-hop secure communications under practical conditions. To guarantee secure communication during the long-distance transmission, the massive MIMO (M-MIMO) relaying techniques are explored to significantly enhance wireless security. The focus of this paper is on the analysis and design of optimal power assignment for a decode-and-forward (DF) M-MIMO relay, so as to maximize the secrecy outage capacity and minimize the interception probability, respectively. Our study reveals the condition for a nonnegative the secrecy outage capacity, obtains closed-form expressions for optimal power, and presents the asymptotic characteristics of secrecy performance. Finally, simulation results validate the effectiveness of the proposed schemes.