Coexistence of delay-sensitive MTC/HTC traffic in large scale networks

The support for mission critical machine-type-communication (cMTC) services is indispensable for the 5th generation (5G) mobile communication systems. As the cMTC and (part of) the conventional human-type-communication (HTC) services are broadband and delay-sensitive services, how to ensure their coexistence is a new and challenging problem. This paper investigates the problem of service-level resource allocation, which decides how cMTC and HTC traffic share a limited amount of radio resource. Considering a large-scale network, we put forth a system model that integrates queuing models and stochastic geometric models to characterize the delay performance in self-interfering scenarios. A service-level resource allocation scheme called load division is proposed. The delay and throughput performance of cMTC and HTC are derived under different resource allocation schemes and priority scheduling policies. We show that compared with the baseline scheme of frequency division, the proposed load division scheme can significantly improve the delay performance of cMTC service, at a cost of slightly degraded MTC and HTC service capacities.