基于时域反射法的土壤水分系统设计  

Soil moisture system design based on time domain reflectometry

作　　者：苏振 胡锦涛[2] 姚学召[2] 王中金 陈海波 李佳[2] SU Zhen;HU Jintao;YAO Xuezhao;WANG Zhongjin;CHEN Haibo;LI Jia(CMA·Henan Key Laboratory of Agrometeorological Support and Applied Technique,Henan Zhengzhou 450003,China;The 27 th Research Institute of China Electronics Technology Group Corporation,Henan Zhengzhou 450047,China)

机构地区：[1]中国气象局河南省农业气象保障与应用技术重点开放实验室,河南郑州450003 [2]中国电子科技集团公司第二十七研究所,河南郑州450047

出　　处：《工业仪表与自动化装置》2024年第5期31-33,共3页Industrial Instrumentation & Automation

基　　金：中国气象局河南省农业气象保障与应用技术重点开放实验室开放研究基金资助(AMF202305)。

摘　　要：土壤水是植物生存和生长发育的基础物质之一,土壤水分的测量对于农业生产具有重要的指导意义。基于时域反射技术测量土壤水分精度高、适应性好等优点,设计了时域反射法测量原理的土壤水分系统。该系统采用STM32F103RET6作为控制器,控制电平进行发射脉冲和采样脉冲的产生和采样,通过对信号采样、处理得到探头在土壤中的传输时间,根据传输时间变化计算出土壤的介电常数和土壤体积含水量。结合样机分别对3种不同质地的土壤进行水分性能实验测试,系统测试的体积含水量与称重法测试的结果接近,测试误差小于2.5%。Soil water is one of the basic substances for plant survival and growth.Soil water measurement has important guiding significance for agricultural production.Based on the advantages of high precision and good adaptability of time domain reflectometry to measure soil water,a soil water system based on time domain reflectometry was designed.The system uses STM32F103RET6 as the controller to control the level to generate and sample the emission pulse and sampling pulse.The transmission time of the probe in the soil is obtained by sampling and processing the signal,and the dielectric constant of the soil and the volume water content of the soil are calculated according to the change of the transmission time.Combined with the prototype,the water properties of three kinds of soil with different textures were tested.The volume water content tested by the system was close to the test result of the weighing method,and the test error was less than 2.5%.

关 键 词：时域反射 土壤含水量 介电常数 

分 类 号：TP23[自动化与计算机技术—检测技术与自动化装置]