基于LoRa和FreeRTOS的数字农田监测系统

Design of digital farmland monitoring system based on LoRa and FreeRTOS

为提高稻田远程监测系统的稳定性,文中设计一种基于LoRa和FreeRTOS的数字农田监测系统。系统由节点、管理芯和手机APP三大部分组成,每个节点和管理芯均带有一个低成本LoRa模块。系统利用节点采集数据,通过LoRa无线传输模块发送到管理芯,将应用APP程序嵌入到FreeRTOS操作系统中。管理芯的MCU为STM32F103ZET6,管理芯接收下行节点发来的数据,通过计算有效积温累计计算现有积温,然后运用积温预测法预估出水稻成长阶段。用户通过APP实时获得稻田成长天数、稻田号、空气温湿度、土壤温度、现有积温和现有水位的数据。为防止数据丢失,保证系统稳定性,在管理芯中加入FLASH存储数据功能,并对传输规约和数据格式进行规定。在测试过程中,手机APP不定时地连接到管理芯的蓝牙上,并无规律地断开连接后,系统运行稳定,方便用户种植。

A digital farmland monitoring system based on LoRa and FreeRTOS is designed to improve the stability of paddy field remote monitoring system.The system is composed of three parts:node,management core and mobile phone APP.Each node and management core have their own low⁃cost LoRa modules.In the system,the node is used to collect data and transmit it to the management core through the LoRa wireless transmission module.The application APP program is embedded into the FreeRTOS operating system.The MCU of the management core is STM32F103ZET6.The management core is used to receive the data sent by the downlink node,calculate the existing accumulated temperature by calculating the accumulation of effective accumulated temperature,and then predict the rice growth stage by means of the accumulated temperature prediction method.By means of APP.users can get the data of paddy field growth days,paddy field number,air temperature and humidity,soil temperature,existing accumulated temperature and existing water level in real time.In order to prevent data loss and ensure the stability of the system,the function of FLASH data storage is added to the management core,and the transmission protocol and data format are stipulated.In the test process,when the mobile phone APP is connected to the Bluetooth of the management core unperiodically and is disconnected irregularly,the system can run stably,which is convenient for users to plant.