IEEE Microwave and Wireless Components Letters · 2009 · 75 citations · 8 references
EngineeringElectrical EngineeringAntennasMicrowave EngineeringStandardized TestingImpedance MatchingMicrostrip CircuitsMicrowave FiltersMicrowave Integrated CircuitsMicrowave ResonatorsMicrowave Transmission LinesBandpass FilteringBandpass FiltersInsertion LossMicrostrip Bandpass FiltersMicrostrip FiltersMicrostrip ResonatorsResonance FrequenciesSpurious Response Suppression
This letter presents a novel compact ultra-wideband (UWB) microstrip bandpass filter with spurious response suppression. A dual-mode ring resonator is constituted to allocate its first two resonant frequencies in the UWB band, and the dual-line parallel-coupled structure is used in this compact UWB filter, which is expected to achieve much tighter coupling degree. Simulated and measured results are found in good agreement with each other, showing a wide passband from 4.9 to 10.9 GHz, 15 dB return loss bandwidth of about 5 GHz, minimum insertion loss of 0.49 dB at 7.3 GHz, and wide upper stopband with more than 20 dB attenuation up to 20 GHz.
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