Energy Efficiency Enhancement for LoRaWAN Networks with Multiple Gateways

LoRaWAN has emerged as a promising and suitable technology for massive machine-type communications. The emerging trend of green communication networking will play a significant role in minimizing power consumption for different battery-powered nodes. The Aloha access scheme used in LoRaWAN leads to a high probability of collision, reducing the network throughput on a large scale. Thus, enhancing the energy efficiency of LoRaWAN networks has become paramount. In this work, we propose a novel spreading factor selection and power control algorithm, named EE-LoRa, to improve the energy efficiency of LoRaWAN networks with multiple gateways. We first devise an optimization problem that maximizes the energy efficiency of the network, defined as a benefit-cost ratio between the network throughput and the consumed energy. Then, power control is applied to tune the transmission power at nodes to the lowest possible levels without affecting the reliability of communications. The simulation results show that EE-LoRa significantly improves the energy efficiency of LoRaWAN networks when compared to legacy LoRaWAN and relevant state-of-the-art algorithms.