Device-to-Device Communication in LTE-A Cellular Networks: Standardization, Architecture, and Challenge

D2D communication in LTE-A cellular networks can improve overall system performance such as throughput and power consumption substantially and can enable and enhance many proximity based applications. This research topic gains great interest in both academic and industrial fields in recent years. The relevant 3GPP standardization on D2D communication has already begun in several discussion groups. We introduce standardization progress in this area, and describe relevant architecture design to enable D2D communication. We also discuss the challenges to incorporate D2D communication into existing cellular networks.