An Interdigital Microwave Sensor Based on Differential Structure for Dielectric Constant Characteristics Measurement

Area of Science:

• Electrical Engineering
• Materials Science
• Sensor Technology

Background:

• Microwave resonator sensors are crucial for material characterization.
• Existing designs often face limitations in sensitivity and defect detection.
• Novel configurations are needed to enhance performance for diverse applications.

Purpose of the Study:

• To propose and validate a novel microwave resonator sensor.
• To investigate the sensor's performance in detecting dielectric properties.
• To assess the sensor's capability for defect identification and material property measurement.

Main Methods:

• Simulated the frequency response of a unique three-resonator, two-feedline sensor design.
• Analyzed sensor sensitivity across different regions and material dielectric constants.
• Fabricated and experimentally validated the sensor against simulation results.

Main Results:

• The first interdigital structure showed the highest sensitivity to dielectric changes.
• Placing materials in specific regions enhanced the linear correlation of frequency response.
• The sensor successfully distinguished material defects and detected subtle dielectric variations.
• Experimental measurements closely matched simulation predictions.

Conclusions:

• The proposed microwave resonator sensor demonstrates significant potential for dielectric sensing.
• The design effectively detects material defects, thickness, and loss tangents.
• This novel sensor configuration offers enhanced performance for material characterization applications.