Design of planar dual-band bandpass filters with stepped-impedance resonators

Abstract

Novel planar dual-band bandpass filters with stepped-impedance resonators have been proposed. The central frequency of dual passbands can be easily controlled by the stepped-impedance resonators. Moreover, two steppedimpedance open stubs can generate transmission zero between two passbands, therefore the isolation can be increased. With the proposed structure, additional transmission zeros will appear around two passbands. In addition, the match between measurement and the theoretical simulation validates the proposed structure.Index Terms -Dual-band bandpass filter, stepped-impedance resonator.

Compact Self-Packaged Dual-Band Filter Using Multilayer Liquid Crystal Polymer Technology

“…6). The amount of coupling is determined by the capacitance created between the metal patches, as a parallel-plates capacitor (5) where 8.854 10 F/m, is the relative dielectric constant of the substrate, is the area of the parallel plates, and is the separation between them. In this case, is determined by the area of or and by the thickness of the dielectric layer between the resonator and the I/O coupling layer.…”

“…The most common approach is to employ multimode resonators and locate the passbands at the resonant frequencies [2], [3], [5]- [7], [11], [12]. The resonant modes are split by means of inter-resonator coupling in order to control the bandwidth.…”