Robust Security Beamforming for SWIPT-Assisted Relay System with Channel Uncertainty

Area of Science:

• Wireless Communication
• Information Security
• Signal Processing

Background:

• Simultaneous Wireless Information and Power Transfer (SWIPT) systems face security challenges from eavesdroppers.
• Channel State Information (CSI) uncertainty between relays and eavesdroppers impacts system security.
• Existing methods may not adequately address robust security under CSI disturbances.

Purpose of the Study:

• To design a robust beamformer for SWIPT relay systems to maximize the worst-case security rate.
• To address physical layer security (PLS) under bounded ellipse CSI uncertainty.
• To optimize security rate subject to relay energy consumption constraints.

Main Methods:

• Formulating a non-convex optimization problem for robust beamforming.
• Introducing a slack variable to decompose the problem into two sub-problems.
• Employing Semidefinite Relaxation (SDR) and S-procedure for optimization.

Main Results:

• The proposed algorithm effectively maximizes the worst-case security rate under CSI uncertainty.
• The method demonstrates superior performance compared to benchmark schemes.
• The approach is shown to be extendable to scenarios with direct source-eavesdropper links.

Conclusions:

• The developed robust beamforming algorithm enhances PLS in SWIPT relay systems.
• The SDR and S-procedure based method provides an effective solution for non-convex optimization problems.
• The findings are significant for secure and efficient wireless communication systems.