Abstract: In order to improve the shortages of data encapsulation standards and lack of communication protocol in intelligent gateway of current agricultural Internet of Things(IoT), a method of intelligent gateway using 3 layer communication protocol was proposed for agriculture, and an agricultural intelligent gateway was designed using this method. Firstly, The application communication protocol, serial communication protocol and node communication protocol were defined, and the 3 layer protocol collaborative completed data encapsulation, processing and transmission of IoT system. Secondly, the intelligent gateway software was designed combining the communication protocol. Finally, the gateway test and analysis were conducted. The experiments showed that the IoT system using intelligent gateway could effectively monitor the agricultural environment information according to communication protocol, such as temperature, humidity, light, and the automatic control of agricultural equipment could be successfully carried out. The validity of communication protocol, and the effectiveness of agricultural data acquisition and equipment control by the Agricultural intelligent gateway of IoT, and the feasibility of building the IoT system of agricultural were verified.

Key words: Internet of Things of agriculture, Zigbee, intelligent gateway, communication protocol

摘要： 为了改善当前农业物联网智能网关数据封装标准和通信协议不统一的不足，提出一种三层通信协议的智能网关设计方法，结合该方法完成了智能网关设计。首先定义了智能网关应用层的通信协议、串口通信协议和节点通信协议，三层协议协同完成农业物联网系统的数据封装、处理和传输；其次结合通信协议完成了智能网关软件设计；最后进行了系统测试和分析，测试结果表明，经智能网关设计的物联网系统能根据通信协议有效监测农业环境的温度、湿度、光照度等农业环境信息，并进行相应设备的自动控制。验证了通信协议的正确性和智能网关在农业物联网数据采集和设备控制的有效性，以及构建农业物联网系统的可行性。

关键词: 农业物联网, ZigBee, 智能网关, 通信协议