부산대학교 도서관

Wireless sensor networks (WSNs), one of the urban sensing technologies, suffer from issues such as, data security, data offloading, bulk data storage, and network coverage which in turn affects urban sensing. Device-to-device (D2D) communication appears to be the most promising candidate for mitigating the problems faced by WSN. Enabling D2D communication in the mm-wave network enhances throughput and bandwidth. However, it suffers from signal degradation due to higher pathloss attenuation. Thus, the proposed scheme applies dynamic mode selection criteria for efficient D2D communication in a 5G mm-wave cellular network (CN). The radius of coverage of D2D users (D2Ds) is derived for switching of the modes, i.e., from inner to outer. The outer mode switching occurs when the D2Ds suffer from extensive pathloss attenuation or with increase in coverage radius. Furthermore, power optimization is done to obtain optimal D2D transmit power thereby, enhancing the data rate. This problem is solved by employing Lagrangian dual optimization technique. The performance metric, coverage probability is also derived which depicts the superiority of the proposed scheme in terms of quality-of-service (QoS) at a higher pathloss attenuation. Simulation results prove the efficacy of the proposed scheme. Finally, the proposed scheme is compared with the state-of-the-art schemes which further validates the superiority of the proposed scheme.