On the development of a new coplanar transmission line based on Gap Waveguide

TL;DR

This paper introduces a novel coplanar transmission line combining gap waveguide technology with traditional coplanar waveguides, demonstrating broadband, low-loss, and low-dispersion performance suitable for millimeter wave systems.

Contribution

It presents a new metamaterial transmission line design with three configurations, validated through simulations and experiments, enhancing integration and efficiency in millimeter wave applications.

Findings

Broadband operation achieved across configurations

Significant reduction in dielectric loss

Prevents substrate mode propagation

Abstract

A combination of gap waveguide technology and the traditional coplanar waveguide is studied in detail and demonstrated experimentally for the first time. This novel metamaterial transmission line is presented in three different configurations and offers a broadband operation, low loss, and low dispersion characteristics. Analytical expressions for its characteristic impedance and effective permittivity are provided and validated by Finite Element Method simulations. The loss and dispersion of the line are analyzed with an Eigenmode solver. The proposed line prevents the propagation of substrate modes in the band of operation at the same time it reduces the dielectric loss in the line due to a higher concentration of the E-field over the air. Moreover, its coplanar layout facilitates the integration of active components. As such, it is considered to constitute a potential key element in the development of more efficient, millimeter wave systems.