Message in Message for Improved LoRaWAN Capacity

The Aloha-like access method is a major limiting factor in LoRaWAN networks, with only 18% of channel utilization at best. It also causes high packet losses when node deployment becomes more massive.In this paper, we propose a technique to enhance the reception process of the LoRaWAN gateways, so that channel utilization can reach values up to 35% in a single LoRaWAN cell.We investigate the benefits of concurrent and preemptive reception at the gateways: the capture effect allows to receive a frame even if it collides with a later frame, whereas Message in Message (MIM) reception allows the gateway to drop the current reception and switch to a new more powerful frame. An implementation in the NS-3 simulator allows us to assess the gains of this approach through extensive simulations.