Covert Communication and Physical Layer Security of RS-Aided Wireless Communication Systems Over $\alpha$-$\eta$-$\kappa$-$\mu$ Fading Channels

In this work, we investigate rate splitting (RS)-aided communication systems over <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\alpha -\eta -\kappa -\mu$</tex-math></inline-formula> fading channels. Specifically, in the presence of a detector or an eavesdropper, the sender uses RS to communicate with legitimate user. With this setup, we analyze the covert performance and derive the exact expressions for the detection error probability (DEP) and covert rate (CR). Meanwhile, the physical layer security (PLS) performance is analyzed, and expressions for secrecy outage probability (SOP) and average secrecy capacity (ASC) are obtained. The accuracy of the theoretical framework is validated by comparing numerical and simulation results. Furthermore, the upper bound on the ASC is obtained. Based on these performance metrics, the system's covert and secrecy performance are evaluated, and the verification results are plotted. The results indicate that the RS scheme can improve the covert performance of communication systems.