Interference Constrained Relay Selection of D2D Communication for Relay Purpose Underlaying Cellular Networks

Relay is a type of application of Device-to-Device (D2D) communication which could optimize the system capacity over the shared uplink (UL) resources while fulfilling prioritized cellular service constrains. In this paper, we consider D2D communication for relay purpose assists User Equipments (UEs) to communicate with Base Station (BS). For constraining the interference from D2D communication to cellular communication in the permitted range by system, we analyze the transmission rate from D2D UE. Further, we deduce a relay selection rule based on the interference constraining. Then, we apply the KM algorithm and the greedy algorithm as two types of selection methods to select different relay for every relay-needed UE according to the selection rule. The numerical simulations results show the sum-rate can be improved by selecting the relays according to the selection rule, and KM algorithm achieves a slightly higher sum-rate than that of greedy algorithm based on the relay selection rule.