Channel Allocation for LoRaWanConsidering Intra-System and Inter-System Interferences

In low power wide area network (LPWAN), intra-system and inter-system interferences have become crucial issues due to a huge number of terminals and the use of the same frequency channels among LPWAN systems. Thus, we propose a channel allocation method for one of the LPWAN systems, long range wide area network (LoRaWAN), according to the radio environment to suppress these interferences. First, a LoRa gateway (GW) estimates an empirical cumulative distribution function (ECD F) of inter-system interference signal power in each frequency channel. Based on the obtained ECDF, the GW allocates LoRa nodes to the frequency channels in ascending order of the inter-system interference time ratio. Then, the GW reallocates the LoRa nodes to the frequency channels by a search algorithm based on a formula of intra-system interference probability so that this probability on each channel becomes lower than a threshold while maintaining the intersystem interference suppression. The simulation results show that our proposed method can suppress packet losses compared to the conventional random channel selection.