Downlink Independent Throughput optimisation in LoRaWAN

In a LoRaWAN network one of the main reasons of packet outage is the destructive interference that is caused by colliding packets. As the network operates with an ALOHA-like channel access setup, there is no easy way of preventing two or more devices transmitting at the same time, possibly generating interference to each other. Different methods are proposed in literature that can be used to decrease this chance. However, most of them require extensive use of downlink messages coupled with involved algorithms at the network side, often for only a marginal improvement in performance. In this paper we analyse some ways to optimise the Packet Delivery Ratio (PDR) of a LoRaWAN network that can be used when setting up a node or a group of nodes, do not involve downlink and can operate without knowledge of other devices in the same network. These are shown to provide a small boost in performance of maximum 10%, which is akin to that of more complex, downlink-dependant schemes, while decreasing the set up complexity considerably.