Performance evaluation of hybrid RIS-aided NOMA network

Abstract

This thesis report offers an in-depth analysis of the performance analysis of a hybrid reconfigurable intelligent surface (HRIS)-assisted non-orthogonal multiple access (NOMA) wireless communication system. The system model comprises a base station, a hybrid RIS, and two users situated at different distances, specifically classified as near and far users. The main objective is to investigate the performance of the considered network by deriving the closed-form expression of outage probability and symbol error rate (SER). The evaluation process is based on the principles of NOMA, which enables multiple users to share the same frequency spectrum by distinguishing them through power levels. The thesis explores the calculation of outage probability, which measures the likelihood that the communication system's performance will fall below a certain threshold. Furthermore, the capacity of the communication system, which indicates the maximum achievable data rate, is assessed along with the symbol error rate (SER), a metric that quantifies the rate of symbol misinterpretation during transmission. Both analytical and simulated methods are used to derive these performance metrics, ensuring a robust validation of the results. The validation process involves physical layer simulations conducted using the Monte Carlo iterative simulation method. This method is well-known for its accuracy in simulating complex systems by performing numerous iterations to approximate the desired outcomes. The results obtained from these simulations provide strong confirmation of the analytical findings, thereby reinforcing the reliability of the proposed performance evaluation framework.