Joint Admission Control and Resource Allocation for Multi-Carrier Uplink NOMA Networks

In this letter, we study the maximum access problem (MAP) for uplink networks with non-orthogonal multiple access technique. Specifically, the MAP is formulated as a mixed integer programming problem with admission control, user clustering, channel assignment, and power control taken into account. To deal with this challenging problem, we first recast it as the maximum independent set (MIS) problem in graph theory. Then, we propose an efficient algorithm to solve this MIS problem in a low complexity manner. Finally, simulation results indicate that our algorithm can greatly improve the number of supported users compared to other schemes. The performance of our algorithm under different channel conditions and non-uniform distributions of users is also investigated.