A millimeter‐wave slow‐wave bandpass filter using compact microstrip stepped‐impedance hairpin resonator with inter‐digital capacitor on GaAs substrate

Abstract

AbstractIn this paper, a new microstrip stepped‐impedance hairpin resonator with interdigital capacitor (IDC) slow‐wave band‐pass filter (BPF) using dielectric supported air‐gapped microstrip line (DAML) of surface micromachining on GaAs substrate is proposed. Unlike conventional slow‐wave filters, the proposed bandpass filters are designed to produce a narrow passband at the fundamental mode of the resonators with small size and a sharp skirt characteristic. The proposed slow‐wave band‐pass filter with IDC is designed to produce a passband of 7.7% at the fundamental frequency of 56 GHz. It shows insertion loss of 3.37 dB, return loss of better than 15 dB, and a stopband characteristic greater than 31 dB within 37.03–45.51 GHz. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1244–1247, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21667