Optimization of LoRaWAN Access control

Abstract Long Range Wide Area Network (LoRaWAN) enables flexible long-range communication with low power consumption which is suitable for IoT applications. LoRaWAN’s performance is due on the one hand to its spreading factor modulation allowing the spread out of communication between end-devices and gateways on different frequency channels and data rates. And on the other hand, to the ability to manage for each node its data rate and its transmission power thanks to the adaptive data rate (ADR) scheme in order to increase the overall network capacity and to maximize the battery life of end devices. However, because of the Aloha access technique adopted by LoRaWAN, the risk of using the same data rate on the same channel is not negligible. Despite the limitation of the duty cycle for each node, the risk of collision is high with the increase of the number of end devices which degrades the LoRaWAN’s performance. In this context, our paper proposes different approaches to improve the performance of LoRaWAN. The first contribution consists in improving the ADR technique to meet the characteristics of a mobile environment. The new mechanism proposed, called VHMM-based E-ADR, consists of adapting the data rate of the end-device according to its position. The second contribution consists in better managing the use of the duty cycle by proposing a dynamic sharing mechanism (Dynamic Duty-Cycle). The last contribution consists in proposing a deterministic access technique to replace Aloha. Our experimental study has shown that our proposals give better results in terms of Packet Delivery Ratio (PDR) and energy consumption than basic LoRaWAN in a mobile environment.