Design of Compact Tri-Band Bandpass Filters Using Assembled Resonators

A novel approach for designing tri-band bandpass filters with independently controllable center frequencies and improved stopband rejection characteristic is presented in this paper. The assembled resonator constructed by a stepped impedance resonator and a common half-wavelength resonator is employed to obtain tri-band response. The stepped impedance resonator is designed to operate at the first and third passbands and the other resonator is designed to operate at the second passband. Two kinds of filter configurations with cascaded and pseudointerdigital formats are proposed. Based on lossless lumped-element equivalent circuit, it is found that both filter structures can introduce transmission zeros between passbands. To verify the proposed approach, two filters are designed and fabricated, the measured results exhibit tri-band bandpass responses with high selectivity.

[1]  Hui Zhao,et al.  Novel triple-mode resonators using split-ring resonator , 2007 .

[2]  C. Quendo,et al.  Planar tri-band filter based on dual behavior resonator (DBR) , 2005, 2005 European Microwave Conference.

[3]  Ching-Her Lee,et al.  Tri-Band Bandpass Filter With Sharp Passband Skirts Designed Using Tri-Section SIRs , 2008, IEEE Microwave and Wireless Components Letters.

[4]  C.-I.G. Hsu,et al.  Tri-band microstrip BPF design using tri-section SIRs , 2007, 2007 IEEE Antennas and Propagation Society International Symposium.

[5]  Ke Wu,et al.  Dual-Band and Triple-Band Substrate Integrated Waveguide Filters With Chebyshev and Quasi-Elliptic Responses , 2007, IEEE Transactions on Microwave Theory and Techniques.

[6]  He Kai Jhuang,et al.  Design of a novel quad-band microstrip BPF using quarter-wavelength stepped-impedance resonators , 2007 .

[7]  Jia-Sheng Hong,et al.  Microstrip filters for RF/microwave applications , 2001 .

[8]  Jen-Tsai Kuo,et al.  Design of microstrip bandpass filters with a dual-passband response , 2005 .

[9]  Yo-Shen Lin,et al.  Design of an LTCC tri-band transceiver module for GPRS mobile applications , 2004, IEEE Transactions on Microwave Theory and Techniques.

[10]  J. Bornemann,et al.  Coupling-Matrix Design of Dual and Triple Passband Filters , 2006, IEEE Transactions on Microwave Theory and Techniques.

[11]  Yue Ping Zhang,et al.  Dual-Band Microstrip Bandpass Filter Using Stepped-Impedance Resonators With New Coupling Schemes , 2006, IEEE Transactions on Microwave Theory and Techniques.

[12]  Q. Chu,et al.  A Compact Dual-Band Bandpass Filter Using Meandering Stepped Impedance Resonators , 2008, IEEE Microwave and Wireless Components Letters.

[13]  J. Kuo,et al.  Design of microstrip bandpass filters with a dual-passband response , 2005, IEEE Transactions on Microwave Theory and Techniques.

[14]  Qing-Xin Chu,et al.  Advanced triple-band bandpass filter using tri-section SIR , 2008 .

[15]  Ruey-Beei Wu,et al.  Design of Dual- and Triple-Passband Filters Using Alternately Cascaded Multiband Resonators , 2006, IEEE Transactions on Microwave Theory and Techniques.

[16]  Qing Xin Chu,et al.  Design of Triple-band Bandpass Filter Using Trn-section Stepped-Impedance Resonators , 2007, 2007 International Conference on Microwave and Millimeter Wave Technology.

[17]  Ching-Her Lee,et al.  Design of a New Tri-Band Microstrip BPF Using Combined Quarter-Wavelength SIRs , 2006, IEEE Microwave and Wireless Components Letters.