<title>Modeling and properties of hybrid integration structures based on unbalanced nonradiative dielectric (NRD) waveguide</title>

Abstract

Non-radiative dielectric (NRD) waveguide, surface-mounted on the top of a relatively thin planar substrate, provides a great flexibility for the integration of planar circuits with NRD-guide. Such an unbalanced NRD-guide may be in direct contact with planar circuits that are fabricated on the same substrate such as microstrip circuits. Besides, NRD-guide may be easily integrated with the microstrip circuits also on a separate dielectric layer by aperture coupling. To facilitate its practical implementation, the dielectric layered surface-mounted NRD-guide structure has been proposed in this paper, this structure is especially suited to the implemented of millimeter-wave integrated circuits. Transitions of planar circuit to surface-mounted NRD-guide have been studied with emphasis on the analysis of potential spurious modes, which provides a basis for the performance-enhanced broadband design and applications. Principal modes generated in the hybrid planar/NRD-guide structure are modeled. Results for transmission and return loss are presented for different transitions. Our investigation indicates than an optimized but uncompensated hybrid planar/NRD-guide integrated transmission should be good enough for many applications over a certain frequency band. For broadband applications, however, spurious mode suppressors in the design of eliminating unwanted modes are required. A design example is also presented.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.