The development of IoT LoRa: A performance evaluation on LoS and Non-LoS environment at 915 MHz ISM frequency

Abstract

Our work has developed the Internet of Things (IoT) LoRa prototype to support the remote measurement of temperature at the frequency of 915 MHz. The device is structured by a temperature sensor, memory storage, data processing and data visualization using Cloud Server on the Web Browser. The performance is evaluated by both LoS and Non-LoS field trial of 14 dBm transmit power. By using the IoT platform of LoRa, end devices with low energy consumption that connected to gateways, shall perform a more efficient data transmission to other devices and network servers. We conduct field trial on Line of Sight (LoS) and Non-LoS condition in the surrounding area of University Indonesia campus. The results have indicated that prototype is working well on both condition, while RSSI may vary from −50 dB to −105 dB. For LoS condition, RSSI is at intervals of −55 dB to −90 dB for distance of 100 meters to 700 meters, while for Non-LoS condition is at intervals of −62 dB to −99 dB for distance of 100 meters to 400 meters. Accordingly, the LoRa is proven to be efficiently used for the IoT applications of both LoS and Non-LoS condition, while a specific design should be adjusted.