Analysis of Outage Probability for Intelligent Reflecting Surface Assisted Downlink NOMA Symbiotic Radio System in κ-μ Fading

Symbiotic Radio (SR) and Intelligent Reflective Surface (IRS) have emerged as pivotal enablers in the realm of next-generation wireless communication systems, attracting substantial interest from both scholarly circles and industry domains. The SR system presents a sanguine technical resolution aimed at surmounting the exacting requisites of the sixth-generation mobile communication technology, which lays great emphasis on transmission rates and device densities. In the present study, our focus resides on an in-depth performance analysis of IRS-facilitated, multiplexed Non-Orthogonal Multiple Access (NOMA) within the purview of SR systems, operating within κ-μ shaded fading channels. The envisaged scenario encompasses a transmitter employing downlink NOMA for signal transmission, while all channel links are subjected to κ-μ fading phenomena. Our analytical journey commences with the derivation of a precise expression encapsulating the outage probability pertinent to the collective receiver framework. Additionally, we advance an approximation technique for the outage probability, ingeniously wielded through a univariate degradation algorithm. We subject our derived findings to rigorous verification via Monte Carlo simulations. The outcomes derived from this empirical validation elegantly affirm the fidelity of our approximation algorithm. Noteworthy observations surface, showcasing that the outage probability attains a state of saturation at elevated Signal-to-N oise Ratio (SNR) regimes. Conversely, we discern that augmenting the count of reflection units imparts a marginal influence upon the outage probability when SNR dwells at lower levels.