Confirmation of Slow-Waves in a Crosstie Overlay Coplanar Waveguide and Its Application to Band-Reject Gratings and Reflectors.
Abstract:
The slow-wave propagation along a new crosstie overlay slow-wave coplanar waveguide has been investigated both theoretically and experimentally. A slow-wave factor observed agrees reasonably well with the theoretical prediction. This structure is used from construction of a frequency-selective distributed Bragg reflectors DBRs with a compact size. The effect of conductor loss is considered. A doubly-periodic band-reject grating has been created from the DBRs and the band-reject phenomenon was observed as predicted. To improve passband characteristics of the grating, a monolithic slow-wave Chebyshev reflector was designed and fabricated. Agreement between theory and preliminary experiment has been confirmed. Based on this theory, a new slow-wave reflector with improved characteristics is proposed and examined. A respectable slow-wave factor and a drastic reduction of conductor loss have been obtained.