A Traffic-Aware Dynamic Frame Adaptation Scheme for LoRaWAN Networks

Abstract

This paper proposes a traffic-aware flexible frame adaptation scheme to improve network capacity in the dy-namic traffic environment of LoRaWAN networks. The proposed scheme determines available frequency channels to be used for data transmission in each channel access period in the frame structure, which consists of a random access period and a reservation-based access period. In the frame structure, a data packet is transmitted by using one of the available channels in the random access period, and resources are assigned to retransmit the data packet in the reservation-based access period when the transmission fails. Due to the transmission policy, it is possible to manage resources suitable for the network environment by estimating network traffic based on the number of data packet successfully transmitted in each channel access period. We compare the network performance of the proposed scheme and legacy LoRaWAN in terms of packet delivery ratio. Our simulation results show that the proposed scheme successfully delivers 4 times more data packets than legacy LoRaWAN by dynamically distributing frequency channels to be used in each channel access period according to the network traffic.