A Broadband Complex Permittivity Probe Using Stepped Coaxial Line

Somporn Seewattanapon, Prayoot Akkaraekthalin

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DOI: 10.4236/jemaa.2011.38050                

Abstract

This paper proposes the stepped coaxial line sensor using the reflection coefficient in microwave range for complex permittivity measuring. The proposed probe is adapted from the conventional SMA connector which is cheap and easy to fabricate. The analysis model of the probe has been done by using FDTD method with the reference material such as the distilled water. The stepped SMA probe presents the accurate result compared with the convention one. The permittivity values of the concentrated alcohols of 10%, 15% and 20% as DUTs at 24^oC in a frequency range of 0.1 GHz to 6 GHz have been measured using the proposed probe. Also, the measurement of salted butter permittivity has been performed. The measured results are more accurate compared with the commercial probe.

Keywords

Complex Permittivity, Reflection Coefficient, Stepped Coaxial Probe

Conflicts of Interest

The authors declare no conflicts of interest.

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