Abstract:
LoRaWAN is an upcoming Low Power Wide Area Network (LPWAN) technology for Internet of Things
implementations in various application domains. Despite its various advantages, LoRaWAN employs an Alohabased
MAC, which in terms of performance cannot guarantee high packet delivery ratio and low latency.
To overcome this issue, we propose a time-slotted scheme, called TS-VP-LoRa, which supports multiple
transmission times and packet sizes at the same time. In TS-VP-LoRa, scheduling is coordinated by the LoRa
gateway, broadcasting beacon frames periodically for the synchronization of LoRa end-devices. A channel
hopping mechanism is also proposed in order to minimize the occurrence of collisions and to evenly split
the transmission load among all channels. TS-VP-LoRa is evaluated and compared to three other MAC-layer
schemes in single gateway simulation scenarios with up to 500 nodes. The proposed scheme has proven to
achieve low latency with high packet delivery ratios, significantly minimize collisions and maintain a relatively
low energy consumption despite the scaling of the LoRa network.