A Formula for Radiation Loss in Substrate Integrated Waveguide

Substrate integrated waveguide, an emerging technology for microwave and millimeter-wave circuits, is affected by three loss mechanisms: ohmic and dielectric losses, standard waveguides, and radiation leakage. While ohmic and dielectric losses can be accurately determined by the analytical formulas of the equivalent rectangular waveguide, no equations are available for radiation leakage. This paper presents the derivation of a formula to calculate the attenuation constant due to radiation leakage in substrate integrated waveguide interconnects.