User-priority-based resource allocation for device-to-device communications in 5G underlaying cellular networks

In 5G cellular networks, device-to-device (D2D) communications help greatly improve spectral efficiency and reduce communication latency. However, interference is intrinsic to D2D communications when sharing spectral resources with cellular users (CUs). On the other hand, D2D is able to bear more and more services, which help user-centred and personalised services become development trends in 5G networks. Against this background, the authors propose a user-priority-based resource allocation scheme in consideration of interference. The scheme first divides the service priority of D2D into four levels based on the principle of satisfying the quality-of-service (QoS) requirements of D2D as much as possible and then performs admission control allowing a D2D pair to use the CU spectral resources according to different priority levels. Next, they develop a maximum throughput scheme for the admissible D2D pair to select a suitable CU partner. Finally, a maximum weighted bipartite matching scheme is adopted. The proposed scheme is compared with a benchmark QoS-aware scheme in terms of the cell radius, distance, and maximum power of the D2D pair. Simulation results show that the proposed scheme is able to notably improve system throughput.