Dual-band bandpass filter with independent passbands using resonant junctions

Abstract

This document presents a dual-band bandpass filter with fully independent passbands. The filter is based on a novel dual-band resonant junction (DBRJ) and λ/2 resonators. This approach allows different filter order at each passband, independent fractional bandwidth tuning, and independent filter response at each band. The DBRJs consist of a short-circuited quarter-wavelength resonator. One prototype is presented with Butterworth and Chebyshev responses and center frequencies at 1.8 and 2.45 GHz.

Keywords:

• dual-band filters
• resonant junction
• microstrip filters
• microwave resonators