Uniplanar one-dimensional photonic-bandgap structures and resonators

• Published in: IEEE transactions on microwave theory and techniques Vol. 49; no. 3; pp. 549 - 553
• Main Authors: Yun, T.-Y., Chang, K.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-03-2001; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Bandwidth; Cavity resonators; Circuit simulation; Coplanar transmission lines; Coplanar waveguides; Defects; Etching; Filling; Impedance; Microwaves; Noise levels; Parametric analysis; Performance analysis; Rejection; Resonator filters; Resonators; Strips
• ISSN: 0018-9480; 1557-9670
• DOI: 10.1109/22.910561

This paper presents uniplanar one-dimensional (1-D) periodical structures, so-called photonic-bandgap (PBG) structures, and defect high-Q resonators for coplanar waveguide, coplanar strip line, and slot line. Proposed uniplanar PBG structures consist of 1-D periodically etched slots along a transmission line or alternating characteristic impedance series with wide band-stop filter characteristics. A stop bandwidth obtained is 2.8 GHz with a stopband rejection of 36.5 dB. This PBG performance can be easily improved if the number of cells or the filling factor is modified in a parametric analysis. Using uniplanar 1-D PBG structures, we demonstrate new high-Q defect resonators with full-wave simulation and measured results. These structures based on defect cavity or Fabry-Perot resonators consist of a center resonant line with two sides of PBG reflectors. They achieve a loaded Q of 247.3 and unloaded Q of 299.1. The proposed circuits should have many applications in monolithic and hybrid microwave integrated circuits.