4$ LuatOS-Based 4G IoT Gateway

This paper^***This paper has emanated from joint research conducted with the financial support of the National Key Research and Development Program of China under Grant No. 2017YFE0135700 and the Bulgarian National Science Fund (BNSF) under Grant No. (KP-06-IP-CHINA/I). presents a low-cost 4G Internet of Things (IoT) gateway, developed with the LuatOS script running framework for integration into the EMULSION IoT platform. The hardware Bill of Materials (BOM) is kept around 4$, making it highly suitable for large-scale IoT deployments. The hardware includes a TTL serial port, built-in GPS, an NTC thermistor for temperature measurement, and an LIS2DH12TR three-axis accelerometer. For 4G connectivity, the Air780EG module, based on the UNISOC EC618 chipset, is employed. For flexible and efficient hardware maintenance, the cloud software of EMULSION is used to support the parameter management and Over-The-Air (OTA) firmware upgrade. The practical use of the gateway was successfully demonstrated in Chongqing city (China) for manhole monitoring and control, and for Water IoT application.