Boosting Energy Efficiency of NB-IoT Cellular Networks Through Cooperative Relaying

NarrowBand Internet of Things (NB-IoT) is a novel radio interface proposed by the Third Generation Partnership Project for addressing the challenging requirements of Machine-Type Communications through a mobile network architecture. Although it natively promises an impressive battery lifetime to constrained devices, advanced methodologies that further reduce energy consumptions are still required. To this aim, this work investigates an extended NB-IoT architecture, embracing the cooperative relaying paradigm. It formulates an optimal relay selection algorithm that minimizes the overall amount of energy consumed in a NB-IoT cell. In addition, it proposes a greedy algorithm able to reach the same goal with a lower computational complexity. System level simulations clearly demonstrate that the adoption of the proposed cooperative relaying paradigm brings to an energy saving up to 30%. Moreover, the greedy approach registers energy consumptions which are only 10% higher than the optimal
strategy.