In this paper, hybrid integration of planar microstrip line and Photonic Band Gap (PBG) structure is proposed for the dielectric characterization of liquids. To implement the PBG structure of the microstrip line, a microfluidic channel with periodic form is introduced into the substrate and filled with different liquids. Based on this configuration, the operation principle of the sensor is based on a frequency shift due to the variation in the center of the bandgap, which in turn changes with the variation of the permittivity of LUT filled in the microfluidic channel. The proposed sensor exploits the behavior of the bandgap as a reflector to construct a resonant structure sensitive to the variation in LUT permittivity. The dimensions of the planar structure are optimized to achieve high precision and discrimination capability. The different empirical expressions describing the complex permittivity with the measured parameters were carried out. To validate the proposed concept, the sensor prototype is designed, fabricated, and tested. The frequency shift related to a change of 3.2 in LUT permittivity corresponds to 180 MHz around 6 GHz. The resonant-mode sensor spans a permittivity range from 1 to 80 with a precision better than 7.2%. The proposed sensor is simple in design and low cost, which may be applied in different applications at the industrial.

中文翻译：

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用于液体介电特性的低成本光子带隙 (PBG) 微带线谐振器

本文提出了平面微带线和光子带隙（PBG）结构的混合集成，用于液体的介电特性。为了实现微带线的 PBG 结构，将具有周期性形式的微流体通道引入基板并填充不同的液体。基于这种配置，传感器的工作原理是基于带隙中心的变化导致的频移，该频移又随着填充在微流体通道中的 LUT 的介电常数的变化而变化。所提出的传感器利用带隙作为反射器的行为来构建对 LUT 介电常数变化敏感的谐振结构。优化平面结构的尺寸以实现高精度和辨别能力。进行了描述具有测量参数的复介电常数的不同经验表达式。为了验证所提出的概念，传感器原型被设计、制造和测试。与 LUT 介电常数变化 3.2 相关的频移对应于 6 GHz 附近的 180 MHz。谐振模式传感器的介电常数范围为 1 到 80，精度优于 7.2%。所提出的传感器设计简单，成本低，可应用于工业上的不同应用。谐振模式传感器的介电常数范围为 1 到 80，精度优于 7.2%。所提出的传感器设计简单，成本低，可应用于工业上的不同应用。谐振模式传感器的介电常数范围为 1 到 80，精度优于 7.2%。所提出的传感器设计简单，成本低，可应用于工业上的不同应用。