Semi-granted Sparse Code Multiple Access (SCMA) for 5G Networks (Invited Paper)

Sparse Code Multiple Access (SCMA) is a promising non-orthogonal multiple access technology for 5G radio access networks. It improves the connectivity and capacity. However, the two multiple access methods of SCMA: granted and grant-free cannot dynamically match the real-time demands since the resources allocated for the granted method and grant-free method are clearly separated with each other. This further deteriorates the system performance. This article proposes a semi-granted SCMA method, by enabling the granted demands and grantfree demands to share the same resources. Simulation results confirm that semi-granted SCMA matches the dynamically fluent demands and significantly improve the throughput of SCMA 5G system.