The Design and Operation of Ultra-Sensitive and Tunable Radio-Frequency Interferometers.
The Design and Operation of Ultra-Sensitive and Tunable Radio-Frequency Interferometers.
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DOI：
10.1109/tmtt.2014.2366134
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发表时间：
2014-12
影响因子：
4.3
通讯作者：
Wang P
中科院分区：
文献类型：
--
作者：
Cui Y;Wang P
介电谱是科学技术研究的重要手段。DS灵敏度和工作频率范围对于许多应用至关重要，包括样品体积小且需要探测各种动态过程的芯片实验室开发。在这项工作中，我们提出了基于功率分配器（PD）和正交混合电路（QHS）的射频（RF）干涉仪的设计和操作考虑。提出这种干涉仪以解决当前DS技术的灵敏度和频率调谐挑战。针对三种常见的传输线传感结构（即，共面波导（CPW）、导体背衬CPW和微带线。一个高灵敏度和稳定的QH为基础的干涉仪是通过测量葡萄糖水溶液的浓度水平，这是十倍低于一些最近的RF传感器，而我们的样品体积是~1 nL。三元混合物溶液的组成分析也证明了与PD为基础的干涉仪。需要进一步的工作来解决系统自动化，高频模型改进和干涉仪缩放等问题。
Dielectric spectroscopy (DS) is an important technique for scientific and technological investigations in various areas. DS sensitivity and operating frequency ranges are critical for many applications, including lab-on-chip development where sample volumes are small with a wide range of dynamic processes to probe. In this work, we present the design and operation considerations of radio-frequency (RF) interferometers that are based on power-dividers (PDs) and quadrature-hybrids (QHs). Such interferometers are proposed to address the sensitivity and frequency tuning challenges of current DS techniques. Verified algorithms together with mathematical models are presented to quantify material properties from scattering parameters for three common transmission line sensing structures, i.e., coplanar waveguides (CPWs), conductor-backed CPWs, and microstrip lines. A high-sensitivity and stable QH-based interferometer is demonstrated by measuring glucose–water solution at a concentration level that is ten times lower than some recent RF sensors while our sample volume is ~1 nL. Composition analysis of ternary mixture solutions are also demonstrated with a PD-based interferometer. Further work is needed to address issues like system automation, model improvement at high frequencies, and interferometer scaling.