Cooperative Secrecy Techniques for Improving Physical Layer Security in NOMA-Based PLC Networks

Power Line Communication (PLC) can achieve noticeable savings in infrastructure deployment time and cost, where it uses the existing power lines for data transmission. Non-orthogonal multiple access (NOMA), is a promising technique that can accommodate multiple users via non-orthogonal resource allocation and so, it can notably improve spectral efficiency and reduce the electromagnetic compatibility of PLC networks. Data privacy is of crucial importance in PLC design due to its broadcasting nature. Therefore, this paper presents several cooperative secrecy techniques for improving physical layer security in NOMA-based PLC networks considering two different security constraints, which are signal eavesdroppers and multiple cooperative eavesdroppers. The secrecy performance is measured in terms of two performance metrics: ergodic secrecy capacity (ESC) and secrecy outage probability (SOP). Monte Carlo simulation results validate the accuracy of the analytical model and derivations.