The Application of LoRaWAN Wireless Communication Protocol in Device Positioning

摘要

Internet of Things (IoT) has been attracting attention from various domains over the last few years. While IoT devices continuously monitor environmental properties and provide remotely controllable functions, the geospatial location of IoT devices is an expensive information to obtain. Whereas Global Positioning System (GPS) is a commonly-used positioning technology, large power-consumption and excessive cost of adding GPS receiver in every IoT device is not realistic. Therefore, this paper presents a design and implementation of a positioning system using a local wireless communication protocol called LoRaWAN. LoRaWAN is a low-power, wireless communication technology recently proposed to transmit information between IoT devices. A device's position can be estimated by monitoring a location dependent parameter (LDP) such as received signal strength indicator (RSSI), which measures received signal strength, time of arrival (TOA), which measures the time duration of signal travel, and time difference of arrival (TDOA), which measures the TOA differences between gateways. While recent studies show that TDOA has a better accuracy than RSSI and TOA requires a signal's start time, this research aims at examining the applicability of TDOA position algorithm on LoRaWAN. The evaluation result shows that the proposed solution shows acceptable positioning accuracy around 100 meters.