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 Utilization Weighted (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 Min-airtime 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.