On the Performance of Noma Systems with Different User Grouping Strategies

• Published in: IEEE wireless communications Vol. 31; no. 1; pp. 56 - 61
• Main Authors: Li, Jinqiang, Chen, Hsiao-Hwa, Guo, Qing
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2024; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Channel coding; Clustering algorithms; Clusters; Delays; NOMA; Nonorthogonal multiple access; Receivers; Resource management; Wireless communication
• ISSN: 1536-1284; 1558-0687
• DOI: 10.1109/MWC.010.2200185

This article investigates several critical issues on the ergodic sum capacity and system outage performance of downlink non-orthogonal multiple access (NOMA) systems with different numbers of users per cluster sharing the same resource. The outcomes from this work suggest that NOMA systems with more users per cluster perform better under a low channel gain, while those with fewer users per cluster perform better under a high channel gain. It discloses a fact that a traditional NOMA system with a fixed user grouping scheme may not be a good choice to deal with complex channel conditions with diverse applications. To address the issue, this article introduces a concept of mixed user grouping NOMA, which outperforms OMA and traditional NOMA significantly. The work in this article lays a foundation for more further investigations on mixed user grouping NOMA systems.