Balanced BPF design using the substrate integrated waveguide

Abstract

In this paper, we present a novel design of a balanced bandpass filter using the substrate integrated waveguide cavity. Two square-shaped substrate integrated waveguide cavities are side-by-side with removing the vias on the common sidewall to form the BPF. Pared microstrip lines are used to construct the balanced ports of the proposed circuit. Slots are utilized to perturb the degenerated modes of TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">102</sub> and TE <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">201</sub> modes. Common-mode signals are managed to be suppressed for a better performance.