Substrate-Integrated Hybrid Metallo-Dielectric Waveguide Architecture for Millimeter-Wave and Terahertz Applications

In millimeter-wave (mmW) and terahertz (THz) applications, the transmission behavior along circuit structures and components, such as radiation and leakage losses, is critical for their overall performances. It is imperative to develop low-loss interconnect and transmission techniques that should be used for the construction of building circuit blocks and elements. In this work, a hybrid metallo-dielectric (MD) waveguide architecture is proposed and studied for the first time. The scheme is made of mixed substrate-integrated dielectric waveguide (SIDW) and substrate-integrated nonradiative dielectric (SINRD) waveguide, which are deployed for the design of specific building parts in consideration of respective transmission properties of the two waveguides. A back-to-back WR3-band prototype based on this hybrid scheme is investigated theoretically and validated experimentally. The hybrid MD waveguide architecture with SINRD is found to outperform the hybrid MD waveguide architecture with substrate-integrated waveguide (SIW) in terms of transmission performance and manufacturing complexity because of the advantageous features of metallized-via-free structure. The presented hybrid MD waveguide architecture shows its potential for developing low-loss highly integrated mmW and THz circuits and systems.