Thru–reflect–line calibration for empty substrate integrated waveguide with microstrip transitions

In past years, a great number of substrate integrated circuits have been developed. Among these new transmission lines, the substrate integrated waveguide (SIW) has received special attention. Although the quality factor and losses of these new integrated lines are better than the planar circuits, these characteristics are worst than in the case of waveguides, mainly due to the presence of dielectric substrate. To improve the performance of the integrated circuits, a new methodology for manufacturing the empty waveguides, without dielectric substrate, but at the same time completely integrated in a planar substrate, has been recently proposed, resulting in the novel empty SIW (ESIW). A low-cost and easy to manufacture thru-reflect-line calibration kit for de-embedding the effect of connectors and transitions when measuring ESIW devices is presented. Results prove the high quality of this calibration kit.