High Selectivity Dual-Band Bandpass Filter with Flexible Passband Frequencies and Bandwidths
Keywords:
Bandwidth, dual-band bandpass filter, passband frequency, transmission zeroAbstract
A short-ended resonator with open stub loaded is presented in this paper. Resonance property is analyzed based on the transmission line theory. Analysis reveals that the odd/even-mode resonance frequency of the proposed resonator can be conveniently controlled. To realize two controllable bandwidths, two different coupling paths are introduced in the filter design. Furthermore, to improve the filter selectivity, the source-load coupling is adopted to create four transmission zeros (TZs) near the edges of the two passbands. Thus, a dual-band bandpass filter (BPF) with high selectivity can be achieved. One filter with two passband frequencies at 1.01 GHz and 2.4 GHz is designed and fabricated to provide an experimental verification on the design method.
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References
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