Uplink Cluster-Based Radio Resource Scheduling for HetNet mMTC Scenarios

Abstract

Current telecommunication networks face a surge in the number of connected Machine-type Communication (MTC) devices, creating an unprecedented disproportionate demand for existing resources, especially when working with a Heterogeneous Networks (HetNets). This demand cannot be addressed adequately as the infrastructure's transition process between different generations is slow. Fourth Generation (4G) relies on Orthogonal Multiple Access (OMA), where a single user can occupy the same sub-channel, Orthogonality offers interference-free communication but for normal loaded scenarios, but under performs in overloaded scenarios. Whereas Fifth Generation (5G) is targeting more spectral efficiency by using the Non-orthogonal Multiple Access (NOMA), allowing MTC devices to share the same resources in frequency and time. However, NOMA medium access techniques in general have a complex scheduler design as group users/devices with aligned correlations. In this study, we formulate and simulate a 4G/5G Uplink scheduler that is based on dual NOMA-OMA. The objective is to achieve a tangible improvement in the spectral and scheduling efficiency of the network. We are able to optimize the system under HetNet objectives and clustering constraints in overloaded scenarios, to examine the limitations of both NOMA and OMA in overloaded scenarios.