A Device-to-Device Communication-Based Disaster Response Network

Device-to-Device (D2D) communication and cognitive radio are among the key technologies that can help to solve the bandwidth bottleneck problem of cellular networks. Such technologies help to maintain the necessary communication between user devices in case of natural disasters and traffic hotspot situations. In this paper, we efficiently exploit the relay selection and cooperative beamforming (CBF) strategies for D2D communication and show that user devices can securely communicate with each other without infrastructure support. We propose a cluster-based hierarchical topology for a multi-hop cooperative relay network, to cover the potentially long distance between the source and the destination. The cluster heads in the proposal act as primary users (PUs) and the cluster members are regarded as secondary users (SUs) or relay nodes. A system model is presented to analyze the problems of relay selection and power allocation in SUs located in different clusters and hierarchical levels. To investigate the efficiency of our proposed model, we define the utilities of PUs employing relay selection and CBF, considering received signal power and latency. We optimize relay selection and beamforming vector by solving a mixed integer nonlinear problem. Numerical results demonstrate the efficiency and robustness of our approach.