Autonomous mode selection scheme for underlay device-to-device communication

Device-to-device (D2D) communication is considered as a key enabling technology in next-generation wireless communication system and thus it has become an intriguing topic for research. This can be seen through the dramatic increase in number of studies on D2D mode selection for the last several years. However, most of existing D2D mode selection researches have focused on various mode selection algorithm based on criteria such as sum throughput, harmonic mean, and distances between user equipments (UEs) assuming that the transmission mode is determined by infrastructure such as evolved Node B (eNB). This is reasonable assumption but it has a crucial problem from the point of implementation, such as significant signaling overhead. This is so because eNB should acquire all Channel Status Information (CSI) corresponding to uplink, downlink and sidelink in order to determine the transmission mode. This process causes more signaling than expected. In this paper, we propose a new type of D2D mode selection scheme, called the autonomous D2D mode selection or UE-based D2D mode selection with the novel criteria. The proposed scheme is expected not only to reduce signaling overhead but also to increase spectral efficiency, which is further demonstrated by the simulation results.