Trusted Transmission: Strengthening Security in CR-Inspired RSMA Systems Amidst Untrusted Users

This study investigates the secrecy performance of a rate-splitting multiple-access system inspired by cognitive radio principles, where the primary user takes on the role of a potential eavesdropper seeking to intercept the secondary user's message. The on-off scheme is utilized to guarantee the transmission of the primary user. We provide closed-form expressions for critical metrics, including the transmission probability of the system under consideration, the secrecy outage probability, and the reliable outage probability of the cognitive user. Monte Carlo simulation results are presented to substantiate our findings and explore the impact of system parameters, such as transmit power and the number of antennas at the base station, on system performance.