A Fourth-order Dielectric Narrow-band Bandpass Filter Using Coaxial Resonator

Abstract

In this paper, a compact fourth-order dielectric bandpass filter is proposed. The filter adopts the mode of linear coupling and is composed of four coaxial resonators and two coupling slots, which are fed by two probes, and the four coaxial resonators are resonated to form a passband. The resonant frequency can be controlled by the radius and height of the resonators, and the inter-cavity coupling is controlled by the width of the coupling windows formed by the coupling slots. At last, the simulation results of the filter show that the filter has narrow bandwidth and good in-band matching performance and out-of-band suppression.