Resource Allocation for Downlink SCMA System Based on Coalitional Game

Sparse code multiple access (SCMA), a newly-developed non-orthogonal multiple access technology, will play a pivotal role in future wireless communication networks. Although SCMA has drawn much attention, some problems still need to be addressed, especially the problem of wireless resource management. This paper analyzes the resource allocation problem of SCMA based downlink system and decomposes the resource allocation process into two steps: codebook combination and codebook allocation. A novel Maximization of High-Quality CodeBook (M-HQCB) algorithm for codebook combination and a coalitional game based Maximization of Group Proportional Fairness (M-GPF) algorithm for codebook allocation are proposed to improve the system throughput. System-level simulation results demonstrate that the combination of M-HQCB and M-GPF has up to 20% throughput gain comparing with the combination of traditional Random Codebook Combination (RCC) and Proportional Fair (PF) codebook allocation scheme at certain expense of fairness.