Design formulas for radiation and crosstalk in substrate integrated waveguides

Substrate Integrated Waveguide (SIW) technology allows to realize waveguide-like components using printed circuit fabrication techniques. An important difference with respect to normal waveguides is the lateral confinement, which is achieved using metalized vias and it does not provide a rigorous shielding. Therefore, a lateral leakage may occur, and this may also cause crosstalk between two adjacent SIW interconnects. This paper presents two formulas that can be used to calculate the attenuation constant due to radiation leakage and the crosstalk for SIW interconnects, respectively. The range of applicability for these formulas are discussed, showing two validation examples against measurement.