Harmonics suppressed substrate-integrated waveguide filter with integration of low-pass filter

Abstract

In this paper, the harmonics suppressed waveguide filter with SIW (substrate-integrated waveguide) structure using inductive windows at satellite communication band is discussed. The SIW structure is realized by via-holes and can be integrated with other circuits oil the same substrate. The SIW filter has the insertion loss of 2.85 dB and return loss of 17.57 dB at the center frequency of 12 GHz. Also, the proposed SIW filter has the harmonics suppression under 20 dB until 30 GHz by inserted low-pass filter (LPF). This harmonics suppressed SIW