Design and experimental results of bilateral interdigital coplanar delay line for MMICs

The design and development of a bilateral interdigital coplanar waveguide (Bi‐CPW) delay line that can be used as a passive device in MMICs is presented in this paper. This Bi‐CPW design is analyzed using the conformal mapping method and realized via an RF‐CMOS‐compatible fabrication process using high‐k dielectric thin film. The Bi‐CPW design shows 180° phase delay at 10 GHz for a 2.8‐mm transmission line. It is shown that a conventional coupler can be implemented in a few mm 2 area without any lumped element. The measured results show the potential for monolithic integration of conventional couplers using Bi‐CPW phase delay line. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 127–130, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11305