稻田水分监测无线传感器设计

Design of Wireless Sensor for Water Monitoring in Rice Field

【目的】为解决现有传感器存在的成本高、通信距离短等问题,设计出一款基于STM32微控制器和LoRa无线通信技术的稻田水分监测无线传感器,该传感器被广泛应用于对农田的监测中。【方法】该传感器由无线通信模块、土壤水分测量模块及水位识别模块组成。采用低频电容法对土壤中的水分进行测量,并将测量得到的信息通过LoRa通信模块进行远距离传输。该传感器整体由太阳能转换模块进行供电,太阳能转换模块采用MPPT节能技术。【结果】使用该传感器对土壤水分进行测试,结果表明,稻田土壤的含水量与输出的电压大致呈线性关系。水位识别测试结果表明,水位识别传感器对水位变化较为敏感,具有良好的线性关系。【结论】该传感器实现了对土壤水分信息的准确采集和数据的稳定传输,并具有较长的续航时间,可实现对稻田水分的实时监测和远程管理。下一步将考虑传感器在复杂环境中的稳定性及对其他农作物的适用性。

[Purposes]In order to solve the problems of high cost and short communication distance of exist⁃ing sensors,a wireless sensor for paddy field water monitoring based on STM32 microcontroller and LoRa wireless communication technology was designed.The sensor is widely used in the monitoring of farmland.[Methods]The sensor was composed of wireless communication module,soil moisture measurement module and water level recognition module.The low-frequency capacitance method is used to measure the moisture in the soil,and the measured information is transmitted over a long distance through the LoRa communication module.The whole sensor is powered by the solar energy conversion module,and the solar energy conversion module adopts MPPT energy saving technology.[Findings]The sensor was used to test the soil moisture.The results showed that the water content of paddy soil was roughly linear with the output voltage.The test results of water level identification show that the water level identification sensor is sensitive to the change of water level and has a good linear relationship.[Conclusions]The sensor realized the accurate collection of soil moisture information and the stable transmission of data,and had a long endurance time,which could realize the real-time monitoring and remote management of paddy field moisture.The next step will consider the sta⁃bility of the sensor in a complex environment and its applicability to other crops.