Width-Constrained Multilayer SIW Components Based on Adjoined Folded SIW Transitions

Stacked, multilayer substrate integrated waveguide (SIW) components are discussed in this contribution. The superordinate design constraint is the limitation of the lateral dimensions determined by the width of the feed SIWs. This is achieved by using a broadband adjoined SIW-to-folded-SIW transition. Based on it, a Riblet-type short-slot quadrature hybrid coupler and a helix-like layer twist of two stacked SIWs are designed, manufactured, and validated in K-/Ka-band by measurements.