Gap waveguide structure in LTCC for millimeter-wave applications

Abstract

Gap waveguide technology represents an emerging and interesting solution for the development of circuits and components operating in the millimeter-wave and submillimeter-wave region. In this new guiding structure the energy is transmitted through the air gap existing between two parallel metal plates with a HIS boundary condition to assure energy confinement. These conditions are implemented by means of a multiplicity of conducting nails periodically distributed on both sides of the guiding media. This paper presents a new of the Gap Waveguide concept using low temperature co-fired ceramic technology (LTCC) in sub-millimeterwave band. Compared to substrate integrated waveguide (SIW) technology, the first interest is the minimization of dielectric losses due to the propagation in air.Furthermore, it is shown that the technological constraints are less severe than for the conception of SIW waveguide (diameter and periodicity of vias). The concept is illustrated with a gap waveguide example working at around 170 GHz.Index Terms-Gap Waveguide, LTCC, SIW, millimeterwave region.I.

Analysis and design of efficient passive components for the millimeter-wave and THz bands

“…The response of such filters is still far from real environment specifications except for very simple, low-cost applications. Integrated solutions of SSGW following [871]- [873] could be useful to improve results in this area. SIW or pseudo-SIW (similar concept but with differences, e. g., via holes more separated than usual, and authors avoid to typecast them as SIW), and advanced designs with classical transmission lines, give an intermedium performance.…”

“…The MRGW topology has been also explored at high frequencies in the mm-wave band. In [871], it is studied the possibility of manufacturing this transmission line using a LTCC process. In addition, the work provides an interesting comparison with SIW in terms of performance and manufacturing challenges.…”

Enhanced fluid characterization in the millimeter-wave band using Gap Waveguide Technology

“…we propose in this work the use of the gap waveguide technology [78]. This technology has been validated to work at the millimeter-wave band in last publications [79]. It presents interesting advantages for the fluidic characterization because we can create fluidic channels in the maximum e-field region.…”

“…After lamination, the green substrates are cut to proper size and are co-fired or sintered to "ceramic" substrates and then separated to the final size [79]. …”