Dispersion and Filtering Properties of Rectangular Waveguides Loaded With Holey Structures
- Resource Type
- Periodical
- Authors
- Palomares-Caballero, A.; Alex-Amor, A.; Padilla, P.; Valenzuela-Valdes, J.F.
- Source
- IEEE Transactions on Microwave Theory and Techniques IEEE Trans. Microwave Theory Techn. Microwave Theory and Techniques, IEEE Transactions on. 68(12):5132-5144 Dec, 2020
- Subject
- Fields, Waves and Electromagnetics
Dispersion
Periodic structures
Mirrors
Phase shifters
Hollow waveguides
Waveguide discontinuities
Rectangular waveguides
Filter
gap waveguide
glide symmetry
hollow waveguide
low dispersion
millimeter-wave
mirror symmetry
multimodal (M-M) transfer matrix
periodic holey structures
phase shifter
- Language
- ISSN
- 0018-9480
1557-9670
This article analyzes thoroughly the dispersion and filtering features of periodic holey waveguides in the millimeter-wave frequency range. Two structures are mainly studied depending on the glide and mirror symmetries of the holes. A parametric study of the dispersion characteristics of their unit cells is carried out. Glide-symmetric holey waveguides provide a higher propagation constant and a low dispersion over a wide frequency range regarding hollow waveguides. This property is particularly useful for the design of low-loss and low-dispersive phase shifters. We also demonstrate that glide-symmetric holey waveguides are less dispersive than waveguides loaded with glide-symmetric pins. Furthermore, we perform a Bloch analysis to compute the attenuation constants in holey waveguides with mirror and broken glide symmetries. Both configurations are demonstrated to be suitable for filter design. Finally, the simulation results are validated with two prototypes in gap-waveguide technology. The first one is a 180° phase shifter based on a glide-symmetric holey configuration that achieves a flat phase shift response over a wide frequency range (27.5% frequency bandwidth). The second one is a filter based on a mirror-symmetric holey structure with a 20-dB rejection from 63 to 75 GHz.