Design of a Planar Sensor Based on Split-Ring Resonators for Non-Invasive Permittivity Measurement

Area of Science:

• Electromagnetics and Materials Science
• Metamaterial sensor design and characterization

Background:

• Material permittivity is crucial for understanding polarization, component identification, and impurity detection.
• Existing methods for permittivity measurement can be complex or costly.

Purpose of the Study:

• To develop a non-invasive technique for material permittivity characterization.
• To design and validate a modified metamaterial unit-cell sensor for enhanced sensitivity and accuracy.

Main Methods:

• Utilized a modified complementary split-ring resonator (C-SRR) with a conductive shield to concentrate the electric field.
• Exploited the perturbation of the fundamental resonant mode excited by microstrip feedlines.
• Enhanced sensor sensitivity four-fold by constructing a tri-composite split-ring resonator (TC-SRR).

Main Results:

• The modified metamaterial sensor successfully excited two distinct resonant modes.
• Perturbation analysis of the fundamental mode accurately determined material permittivity.
• The TC-SRR configuration demonstrated a four-fold increase in sensitivity.

Conclusions:

• The proposed non-invasive technique using a modified metamaterial sensor offers an accurate and cost-effective solution for permittivity measurement.
• The enhanced sensitivity of the TC-SRR design makes it suitable for precise material characterization.