volume | PIER Journals

Abstract

A four-pole elliptic function compact bandpass filter is designed by using interdigital hairpin resonator and step-impedance hairpin resonator. The miniaturized band-pass filter is also implemented using high permittivity dielectric substrate. The full-wave simulator IE3D is used to design the compact hairpin resonator, and to calculate the coupling coefficient of the basic coupling strictures. The responses of the fabricated filters using Al₂O₃(ε_r = 9.7, Q×f = 350000 GHz) and 0.6Sm(Co_1/2Ti_1/2)O₃-0.4CaTiO₃ (ε_r=37, Q×f = 43000 GHz) dielectric substrates are designed at a center frequency of 2 GHz. The size of the compact hairpin filter using 0.6Sm(Co_1/2Ti_1/2)O₃-0.4CaTiO₃ ceramic substrate, as compared to that of a compact hairpin filter using Al₂O₃ ceramic substrate, is reduced in size by 45%. The compact size and good agreement have been obtained between simulations and implementation results.

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Prof. Cheng-Hsing Hsu

Dr. Hsuan-An Ho

Dr. Chung-I Hsu