Utilization-Weighted Algorithm for LoRaWAN Capacity Improvement for Local Smart Dairy Farms in Ratchaburi Province of Thailand

This paper presents Long Range Wide Area Network (LoRaWAN) scalability improvement
using the UtilizationWeighted (UW) spreading factor (SF) assignment algorithm that was logically designed
to equalize SFs usage based on the M/D/1 queuing model. The test area containing dairy farms housing
approximately 1,200 cows in Photharam district, Ratchaburi province of Thailand, was selected to simulate
the proposed algorithm and evaluate its performance. The suburban Hata path loss model was chosen as a
reference to incorporate the actual network environment into the simulation. It is then carefully optimized
by factoring in the empirical path loss data collected in a 12-kilometer radius of the gateway location
and then applying the parameters adjustment (PA) tuning method that proved to provide lower root mean
square errors (RSMEs) than the RMSE tuning method. Two key performance indicators, including packet
received rate (PRR) and energy consumption, were compared between the UW algorithm and the Minairtime
or traditional method. The simulation was focused on the 2-kilometer radius wherein most dairy
farms reside. It was found that the UW algorithm provided higher PRR without jeopardizing the energy
consumption comparing to the traditional LoRaWAN, due to the more equalization of SFs employment. The
maximum improvement of PRR was around 43.90%, while the energy consumption level was maintained at
approximately 113 J per day per node.