Joint Mode Selection and Resource Allocation for Relay-Assisted Device-to-Device Networks

摘要

Device-to-device (D2D) communication considerably advances proficiency in a wireless network system. However, the emerging of D2D can cause crucial interference problem in Advanced Long-Term Evolution (LTE) network and the quality of service (QoS) problem. It is, therefore, necessary to develop an effective algorithm to control and manage the resources of the system to avoid harmful interference in the system. Consequently, we focus on the joint transmission mode, channel and power allocation of communication links in a D2D communication network. A D2D link can transmit in one of the different transmission modes (i.e., direct, indirect, relay, and dedicated mode). To solve the problem, we propose a coalitional game model for finding an optimal combination of communication links along with a channel and power allocation which can simultaneous share the same channel. Each D2D link firstly selects a transmission mode. All links in the same transmission mode form as a coalition. With a cooperative game approach, each D2D link within the same coalition cooperatively selects the channel to achieve the minimum total transmission powers while satisfying the data rate requirement of each link. To solve the joint power allocation and channel selection, we also develop a greedy algorithm with low complexity. Each D2D link can change its coalition (i.e., transmission mode) to a better coalition that provides the lower cost (i.e., a function of the transmission power and the channel occupancy cost depending on the D2D link's communications mode) as long as there is no other D2D link getting the worst-off cost. Our proposed framework can improve the average energy efficiency by 39% and reduce the computation time by 96% compared with the existing work.