Soil moisture system design based on time domain reflectometry
Soil water is one of the basic substances for plant survival and growth.Soil water measure-ment has important guiding significance for agricultural production.Based on the advantages of high pre-cision 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 test-ed.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％.
time domain reflectometrysoil moisture contentdielectric constant
万方数据
维普
