Bandpass Filter With Tunable Bandwidth Using Quadruple-Mode Stub-Loaded Resonator
Authors:
- 22 March 2012
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in IEEE Microwave and Wireless Components Letters
- Vol. 22 (4) , 176-178
Abstract
In this letter, a novel quadruple-mode resonator bandpass filter (BPF) with tunable bandwidth is proposed. By using two types of microwave varactors to tune the resonant frequencies and transmission zeros (TZs), the high-side edge of the passband and low-side edge of the passband can be separately varied. Therefore, the bandwidth could be tunable with reasonable adjust of the values of varactors. Theoretical expressions have been derived for the resonant frequencies and the TZs. The measured results of the BPF show that the fractional bandwidth can be tuned from 22% to 34% at a fixed centre frequency 2.0 GHz with a return loss better than dB. The tested results show good agreement with simulated results.Keywords
This publication has 10 references indexed in Scilit:
- Compact and High-Selectivity Microstrip Bandpass Filters Using Triple-/Quad-Mode Stub-Loaded ResonatorsIEEE Microwave and Wireless Components Letters, 2011
- Ring Resonator Bandpass Filter With Switchable Bandwidth Using Stepped-Impedance StubsIEEE Transactions on Microwave Theory and Techniques, 2010
- Varactor-Tuned Dual-Mode Bandpass FiltersIEEE Transactions on Microwave Theory and Techniques, 2010
- Compact Low-Loss Reconfigurable Bandpass Filter With Switchable BandwidthIEEE Microwave and Wireless Components Letters, 2010
- A Novel Microstrip Filter Using Three-Mode Stepped Impedance Resonator (TSIR)IEEE Microwave and Wireless Components Letters, 2009
- Low-Loss Two-Pole Tunable Filters With Three Different Predefined Bandwidth CharacteristicsIEEE Transactions on Microwave Theory and Techniques, 2008
- Dual-Mode Microstrip Open-Loop Resonators and FiltersIEEE Transactions on Microwave Theory and Techniques, 2007
- Tunable combline filter with continuous control of center frequency and bandwidthIEEE Transactions on Microwave Theory and Techniques, 2005
- Reconfigurable bandpass filter with a three-to-one switchable passband widthIEEE Transactions on Microwave Theory and Techniques, 2003
- New compact bandpass filter using microstrip /spl lambda//4 resonators with open stub inverterIEEE Microwave and Guided Wave Letters, 2000