Relative dielectric constant measurement system for natural soil in microwave region

微波区天然土壤相对介电常数测量系统

• 批准号: 20560393
• 负责人: KIMURA Hiroshi
• 金额: $ 2.91万
• 依托单位: Gifu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2008
• 资助国家: 日本
• 起止时间: 2008 至 2010
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-20560393/
• 关键词: 計測工学; 誘電体物性; マイクロ波; 土壌

An open-ended coaxial probe and its data processing method are developed for measuring the dielectric constant of natural soil. An equivalent circuit of the probe is built based on its geometry, and relations among the reflection coefficient(measurement), the complex dielectric constant of the medium filled in the probe and others are derived. Using the relations, a relative dielectric constant of the medium is calculated. Measurements of real and imaginary parts of the dielectric constant with different water contents are demonstrated. In radar remote sensing, measurement of soil water content is an important issue, where the relation, radar backscatter⇔dielectric constant⇔water content is utilized. The dielectric constant is directly related to microwave scattering, and furthermore this probe and method are applicable for liquid media. This research is expected to expand its use in the field of microwave scattering.

研制了一种用于测量天然土壤介电常数的开口同轴探头及其数据处理方法。根据探头的几何形状，建立了探头的等效电路，导出了探头的反射系数（测量值）、探头内介质的复介电常数等参数之间的关系。使用该关系，计算介质的相对介电常数。演示了不同含水量的介电常数的真实的和虚部的测量。在雷达遥感中，土壤含水量的测量是一个重要的问题，其中利用的关系，雷达后向散射惠介电常数惠含水量。介电常数与微波散射直接相关，而且该探头和方法适用于液体介质。该研究有望扩大其在微波散射领域的应用。