Compact UWB bandpass filter using localized substrate integrated artificial dielectric (L-SIAD)

In this paper, a multiple-mode resonator (MMR) using localized substrate integrated artificial dielectric (L-SIAD) is proposed to construct a compact ultra-wideband (UWB) bandpass filter (BPF). Due to the electromagnetic bandgap (EBG) property of L-SIAD, this MMR provides a broad upper stopband for the BPF. Meanwhile, broadside coupled-lines are used to provide tight coupling and sharp skirt for the BPF by the coupling transmission zero. Finally, such a UWB BPF is designed and fabricated. The measured results demonstrated that this filter has broad upper stopband, sharp rejection skirt, and low insertion loss in passband with flat group delay.