451. Development of a Current Injection—Type Impedance Measurement System for Monitoring Soil Water Content and Ion Concentration.
- Author
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Shigemasu, Ryuki, Teraoka, Yuki, Ota, Satoshi, Hirano, Harutoyo, Yasutomi, Keita, Kawahito, Shoji, and Futagawa, Masato
- Subjects
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SOIL moisture measurement , *SQUARE waves , *PARALLEL electric circuits , *MOISTURE measurement , *RAYLEIGH waves - Abstract
This study was conducted with the aim of developing a circuit system that enables the measurement of the moisture content and ion concentration with a simple circuit configuration. Our previous studies have shown that soil can be represented by an equivalent circuit of a parallel circuit of resistors and capacitors. We designed a circuit that can convert the voltage transient characteristics of the soil when a current is applied to it into a square wave and output frequency information and developed an algorithm to analyze the two types of square waves and calculate R and C. Normal operation was confirmed in the range of 10 kΩ–1 MΩ for the designed circuit, and the calculation algorithm matched within a maximum error of 5%, thus confirming the validity of the program. These successfully confirmed the changes in the water content and ionic concentration. The soil moisture content measurement succeeded in measuring a maximum error of about 10%, except at one point, and the soil ion concentration measurement succeeded in measuring a maximum error of 6.6%. A new, simple, noise-resistant moisture content and ion concentration measurement circuit system with square wave output has been realized. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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