A Multi-interface Data Acquisition Gateway Based on 6LoWPAN for Multi-sensor Situation

The IPv6 over Low Power Wireless Personal Area Network (6LoWPAN) has been used in many areas. How to reduce the number of 6LoWPAN nodes in multi-sensor situation needs to be studied. This paper describes the design and implementation of a multi-interface data acquisition gateway based on 6LoWPAN. The gateway has 6 kinds of data acquisition interfaces, including RS485, CAN, LoRa, ZigBee, 4G and GPRS. Modbus is the protocol of these interfaces' application layer. The gateway is designed with a modular approach, which is easy to be extended or tailored for other applications. Since the acquisition task quantity of the gateway changes with the configuration, and has the characteristics of multi-task synchronization and realtime response, the software design of the gateway is based on the FreeRTOS real-time system to meet the above requirements. In the 6LoWPAN network, the acquisition gateway acts as a 6LoWPAN node. After configuring the gateway through serial port, the gateway first reads sensor data from the interface and then sends the data to the 6LoWPAN module. The test results show that the gateway can read the sensor data correctly according to the configuration requirements. The purpose of using the multi-interface and bus protocol is to reduce the number of 6LoWPAN nodes required in the multi-sensor situation, thus reducing the routing complexity of the 6LoWPAN network, system cost and power consumption.