An integrated transition of microstrip to substrate integrated nonradiative dielectric waveguide based on printed circuit boards

Multilayer circuit is essential for hybrid integrated technology. In this paper, a triple-layer transition of microstrip line to substrate integrated nonradiative dielectric waveguide (SINRD) is presented, of which the SINRD waveguide is fabricated directly on PCBs through air holes. Due to this integrated transition, the realization of hybrid integrated systems directly connected with planar circuits is possible. Furthermore, to use SINRD waveguide fabricated on PCBs instead of traditional NRD is because that mechanism and integration of the former are much easier. In addition, a double-layer transition is also proposed to compare with the triple-layer transition and to demonstrate that the leakage loss from the uncovered SINRD waveguide is negligible. Finally, the simulation results of the transition of conventional NRD guides are compared to those of SINRD guides. Good agreements can be found.