Optimization of Secure Space Diversity-based HDAF Cooperative Relay Systems using SADEA

Abstract

Security and relay selection are key issues in modern wireless communication networks, particularly with Rayleigh fading mobility. Conventional strategies for addressing the issue remain subject to eavesdropping, and optimal relay selection can be computationally expensive. To address these issues, this study proposes the secure hybrid decode-amplify-and-forward (HDAF) cooperative relay protocol. To improve relay selection while reducing computing complexity, the proposed protocol incorporates Surrogate Model Assisted Differential Evolution for Antenna Synthesis (SADEA), which combines antenna synthesis with differential evolution. In this study, performance is tested using Bit Error Rate (BER) and Secrecy Outage Probability (SOP) to determine the intelligibility of transmitted information. The study additionally monitors Information Security (IS) metrics using Exclusive OR (XOR) operator at relays to prevent leaking to eavesdroppers. Equal Gain Combining (EGC) improves signal reception, whereas relay selection depends on SNR value. Comparisons with conventional relay systems based on MATLAB show that the new protocol outperforms BER and SOP. The SADEA method, Gaussian processes, and differential evolution reduce the computational cost of building constant, secure wireless networks. This study demonstrates that the secure HDAF protocol can enhance physical layer security in wireless networks.