volume | PIER Journals

Abstract

This paper proposes a compact microstrip bandpass filter (BPF) with high selectivity. A folded stepped-impedance resonator (SIR) of which the high impedance part is realized by a coplanar waveguide on the ground layer is introduced to the filter design for miniaturization. Furthermore, source-load coupling is implemented by extended tapped lines (ETLs). High selectivity with four transmission zeros (TZs) can be achieved. The analysis of the filter is presented based on atransmission line circuit model and even- and odd-mode analysis method. An experimental filter with the size of 0.15λ_g*0.13λ_g (where λ_g is the guide wave-length at the center frequency) is designed to validate our methods.

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Dr. Yi-Qiang Gao

Dr. Wei Shen

Dr. Liang Wu

Dr. Xiao-Wei Sun