Device Discovery in D2D Communication: Scenarios and Challenges

Device to Device (D2D) communication is expected to be an essential part of 5G cellular networks. D2D communication enables close-proximity devices to establish a direct communication session. D2D communication offers many advantages, such as reduced latency, high data rates, range extension, and cellular offloading. The first step to establishing a D2D session is device discovery; an efficient device discovery will lead to efficient D2D communication. D2D device further needs to manage its mode of communication, perform resource allocation, manage its interference and most importantly control its power to improve the battery life of the device. This work has developed six distinct scenarios in which D2D communication can be initiated, considering their merits, demerits, limitations, and optimization parameters. D2D communication procedures for the considered scenarios have been formulated, based upon the signal flow, containing device discovery, resource allocation, and session teardown. Finally, latency for each scenario has been evaluated, based on propagation and processing delays.