Compact dual‐band bandpass filters based on a novel defected ground spiral resonator

A novel defected ground structure spiral resonator with two spiral stubs and a center stub was presented in this article. Full-wave simulation was used to investigate the working principle of the resonator. The results show that the spiral resonator has two operating modes, so that it can produce two resonant frequencies. It is also found that it is convenient to control the two resonant frequencies by adjusting the dimensions of the two spiral stubs and the center stub. A dual-band bandpass filter (BPF) was designed using two resonators of this type and a T-shaped coupling node, having a bandwidth of 4.5% at 1.87 GHz and a bandwidth of 3.3% at 2.43 GHz. The measured results of the designed dual-band BPF agree well with the simulated responses. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1636–1640, 2015

[1]  Lei Zhu,et al.  Compact dual-band bandpass filter using defected microstrip structure for GPS and WLAN applications , 2010 .

[2]  Raafat R. Mansour,et al.  Design of superconductive multiplexers using single-mode and dual-mode filters , 1994 .

[3]  Lei Zhu,et al.  Design of a Compact Dual-Band Bandpass Filter Using Coupled Stepped-Impedance Resonators , 2014, IEEE Microwave and Wireless Components Letters.

[4]  Jong-Sik Lim,et al.  Equivalent circuit modelling of spiral defected ground structure for microstrip line , 2002 .

[5]  Ji-Chyun Liu,et al.  Inter-digital coupled dual-mode patch resonator with crossed-island configuration for tri-band filter design , 2014 .

[6]  Xuehui Guan,et al.  Dual-Band Superconducting Bandpass Filter Using Embedded Split Ring Resonator , 2013, IEEE Transactions on Applied Superconductivity.

[7]  Yong Fan,et al.  Compact dual‐band bandpass filter based on mixed electric and magnetic coupling , 2014 .

[8]  C. Hsue,et al.  Dual-band bandpass filters using equal-length coupled-serial-shunted lines and Z-transform technique , 2004 .

[9]  Li Gao,et al.  High-Selectivity Dual-Band Bandpass Filter Using a Quad-Mode Resonator With Source-Load Coupling , 2013, IEEE Microwave and Wireless Components Letters.

[10]  I. Wolff Microstrip bandpass filter using degenerate modes of a microstrip ring resonator , 1972 .

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

[12]  Sang-Min Han,et al.  Flexible Microwave Tag System Based on DGS Multiple Resonators , 2013 .