Ad-Hoc Double-Extended-Bitten Ridge Waveguide for Broadband Dielectric Characterization of Lossy Dispersive Solid and Semi-Solid Materials

Dielectric characterization of materials is an essen- tial component of a wide range of applications, from antenna design to biomedical modeling. However, it might be susceptible to sample manufacturing and procedural errors that affect the reproducibility, reliability, and accuracy. To mitigate these issues, this paper proposes and examines an ad-hoc double- extended-bitten ridge waveguide (DEB-RW) aimed for broad- band dielectric characterization of lossy dispersive materials, and compares it with a baseline double-ridge waveguide (D-RW). The DEB-RW reduces field instabilities in the high-sensitivity region due to sample misalignment and air gaps, enhancing both the accuracy and repeatability of dielectric property retrieval, retaining the advantages of the D-RW in terms of operational frequency band, 1−4 GHz. Finally, a gap waveguide implementation is proposed to simplify the measurement system while maintaining performance.