Highly Accurate Liquid Permittivity Measurement using Coaxial Lines

This paper presents a novel complex permittivity measurement system for low-loss and lossy liquids based on the use of multiple frequencies. The system includes a designed coaxial structure that contains the liquid under test and a reconstruction algorithm. Fabrication results show the validity of the method with a higher accuracy level compared to the commonly used open-ended coaxial technique, which makes the proposed method an attractive candidate for highly precise and cheap liquid permittivity identification.