基于TDR的土壤水分传感器设计与试验

针对农田环境下观测作物生长所需土壤水分变化的实际需要，研制了一种基于TDR原理的新型土壤水分传感器。运用等效采样原理和窄脉冲激励来构建高速波形重建方法，同时设计开发 PC 上位机软件，通过蓝牙技术将TDR测量设备与上位机软件进行通信，测量结果可实时无线传输。为验证其性能，进行了4种不同质地土壤的标定试验，并与波兰Easy Test 公司的FOM／mts型TDR进行对比。试验结果表明：该传感器在土壤含水量非饱和状态下，测量结果与土壤实际含水量线性相关度达到0．97以上，且几乎不受土壤质地影响，具有一定的推广应用价值。

Design and Experimental Research of an Instrument for Soil Moisture Sensor Based on TDR

For the actual need for observing the environment required for the growth of crops under farmland soil moisture regime ,developed a new type of soil moisture sensor based on the principle of TDR .Equivalent sampling theory and using incentives to build high-speed narrow pulse waveform reconstruction method , and PC software design and development of PC, using Bluetooth technology TDR measurement equipment and PC software to communicate real -time wireless trans-mission of measurement results .To test its performance , conducted four different calibration test soil texture , and Easy Test with Poland's FOM /mts type TDR for comparison .The test results showed that the soil moisture sensor in a non-saturated state , the measurement results with actual soil moisture linear correlation reaches 0.97 or more, and almost free from influence of soil texture , has a certain application value .