Miniaturized Bandpass Filter Using Quarter SIW Resonator With Elliptic Defected Structure.

A novel quarter substrate integrated waveguide resonator (QSIWR) with an etched elliptic defected structure (EDS) to reduce its resonant frequency employs electric coupling in the main path and magnetic coupling in the cross-coupled path to realize a miniature cross-coupled bandpass filter (BPF) with a size reduction greater than 88 percent. The filter possesses a transmission zero (TZ) in the upper stopband, which improves selectivity. [ABSTRACT FROM AUTHOR]