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Research on the Dielectric Constant Sensor System Based on the Short-Ended Transmission Line
Haoyang Shi1, Xuchun Zhang1, Chuan Sheng1
1Air Defense and Anti-Missile Academy, Air Force Engineering University, Xi'an 710051, China.
Sensors (Basel, Switzerland)
|August 13, 2026
Summary
A new sensor system accurately measures the dielectric constant of solids and liquids. This portable device uses a transmission line probe and control circuit for precise material characterization.
Area of Science:
- Electrical Engineering
- Materials Science
- Electromagnetics
Background:
- Accurate dielectric constant measurement is crucial for material characterization.
- Existing methods often require auxiliary equipment or are limited in material type.
- Development of a portable and versatile dielectric measurement system is needed.
Purpose of the Study:
- To present a novel sensor system for independent dielectric constant measurement of powdered solids and liquids.
- To design and validate a low-cost, portable sensor system.
- To analyze the system's performance and potential interference factors.
Main Methods:
- Utilizing a short-ended transmission line based on air coplanar waveguide as the sensing probe.
- Introducing a parallel resistor to influence the resonance frequency based on the material under test's dielectric constant.
- Developing a dedicated control circuit with integrated control, RF chips, and a detector.
Main Results:
- The system accurately characterized the dielectric constant of six different materials (powdered solids and liquids).
- The proposed sensor system demonstrated a simplified design and higher measurement precision compared to existing systems.
- Resonance frequency shifts directly correlated with variations in the dielectric constant of the material under test.
Conclusions:
- The developed sensor system offers a reliable and accurate method for dielectric constant measurement of diverse materials.
- The system's portability, low cost, and high precision make it suitable for various applications, including radio frequency identification.
- Further analysis confirmed the system's validity and identified key factors influencing measurement accuracy.
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