Analyzing Energy Efficiency and User Sum Rate in NOMA System: A Performance Assessment

Non-Orthogonal Multiple Access (NOMA) represents a multiplexing technique within wireless communication systems, strategically employed to amplify both system capacity and spectral efficiency. This approach enables numerous users to seamlessly share the same frequency band concurrently, with divisions established based on their channel strengths. In the NOMA framework, users are classified into two categories: stronger and weaker. Stronger users receive elevated power allocation, while their weaker counterparts operate with comparatively lower power. Clusters of users are formed within the NOMA structure, encompassing a variety of individuals. The technique integrates widely recognized methods such as superposition coding (SC) and successive interference cancellation (SIC). These techniques collectively optimize resource utilization and heighten data rates for users. Consequently, NOMA stands as a promising avenue for facilitating multi-user access in upcoming wireless network generations. However, the realization of NOMA's potential necessitates the resolution of several critical issues, including inter-user interference, power allocation, channel estimation, user scheduling, and complexity. These factors contribute significantly to the accurate evaluation of NOMA's performance. Within the scope of this study, the efficacy of NOMA is meticulously scrutinized. This evaluation centres on the average sum rate of users and the average energy efficiency. The assessment encompasses various NOMA configurations, including Fully SC-SIC NOMA, Frequency Division NOMA (FD-NOMA), and Frequency Division Multiple Access (FDMA). These configurations accommodate diverse multiplexed user scenarios, each with distinct minimum rate requirements on individual sub-channels.