Transmit Power Allocation for Physical Layer Security in Cooperative Multi-Hop Full-Duplex Relay Networks

Area of Science:

• Wireless communication networks
• Information security
• Signal processing

Background:

• Multi-hop relay networks are crucial for extending wireless coverage.
• Full-duplex relays (FDRs) can transmit and receive simultaneously, enhancing efficiency.
• Ensuring secure data transmission against eavesdroppers is a significant challenge in wireless networks.

Purpose of the Study:

• To develop optimal power allocation strategies for secure transmission in multi-hop decode-and-forward (DF) full-duplex relay (FDR) networks.
• To maximize the achievable secrecy rate under an overall transmit power constraint.
• To address scenarios with both perfect and imperfect self-interference cancellation.

Main Methods:

• Derivation of an optimal power allocation (OPA) strategy using Karush-Kuhn-Tucker (KKT) conditions for the perfect self-interference cancellation (PSIC) case.
• Proposal of a transmit power allocation scheme using geometric programming (GP) for imperfect self-interference cancellation (ISIC).
• Cooperative beamforming techniques to null out signals at eavesdroppers.

Main Results:

• An OPA strategy was derived for the PSIC case, maximizing the secrecy rate.
• A GP-based power allocation scheme was proposed for the ISIC case.
• Numerical results validated the effectiveness of the proposed power allocation schemes in enhancing secrecy rate performance.

Conclusions:

• The proposed power allocation schemes effectively enhance secrecy rates in multi-hop DF-FDR networks.
• The study provides viable solutions for secure wireless communication under varying self-interference conditions.
• The findings contribute to the design of more secure and efficient wireless relay systems.