Hao Honggang, Wang Dexu, Wang Zhu, Yin Bo, Ruan Wei
College of Electronic Engineering, Chongqing University of Posts and Telecommunications, Chongqing 400065, China.
Sensors (Basel). 2020 Sep 29;20(19):5598. doi: 10.3390/s20195598.
In order to improve the sensitivity of liquid dielectric constant measurements, a liquid dielectric constant sensor based on a cubic container structure is proposed for the first time. The cubic container, which consists of a dielectric substrate with a split resonant ring (SRR) and microstrip lines, can enhance the electric field intensity in the measuring area. High sensitivity can be obtained from measuring the dielectric constant with the characteristics of the structure resonate. The research results show that the resonant frequency of the sensor is shifted from 7.69 GHz to 5.70 GHz, with about a 2 GHz frequency offset, when the dielectric constant of the sample varied from 1 to 10. A resonance frequency offset of 200 MHz for the per unit dielectric constant is achieved, which is excellent regarding performance. The permittivity of oil with a different metal content is measured by using the relation between the fitted permittivity and the resonant frequency. The relative error is less than 1.5% and the sensitivity of measuring is up to 3.45%.
为了提高液体介电常数测量的灵敏度，首次提出了一种基于立方容器结构的液体介电常数传感器。该立方容器由带有分裂谐振环（SRR）的介电基板和微带线组成，可增强测量区域内的电场强度。通过利用结构谐振特性测量介电常数可获得高灵敏度。研究结果表明，当样品的介电常数从1变化到10时，传感器的谐振频率从7.69 GHz偏移到5.70 GHz，频率偏移约2 GHz。实现了每单位介电常数200 MHz的谐振频率偏移，在性能方面表现出色。利用拟合介电常数与谐振频率之间的关系测量了不同金属含量油的介电常数。相对误差小于1.5%，测量灵敏度高达3.45%。
