In this paper, a novel microstrip structure is developed to realize a dual-band bandpass filter. The proposed bandpass structure uses a microstrip resonator with two independently controlled resonance frequencies producing two frequency bands of interest controlled by adjusting the dimensions of the resonator. Parametric analysis is performed on the structure to determine the optimum dimensions to obtain the desired frequency response and is explained in the paper. The dual-band bandpass filter developed in this paper exhibits dual operating frequencies at 1390 MHz and 2520 MHz with 9.85% and 9.92% fractional bandwidths respectively. We achieved a compact second-order dual-band bandpass filter with controllable resonance frequencies and low insertion losses in the passband with high selectivity. The measured results are in good agreement with simulated results. Additionally, it can be easily fabricated and can be used in applications where miniaturization and compatibility with microstrip technology are of primary concern.
2. Llorens, D., P. Otero, and C. Camacho-Penalosa, "Dual-band, single CPW port, planar-slot antenna," IEEE Trans. Antennas Propagat., Vol. 51, No. 1, 137-139, Jan. 2003.
3. Hashemi, H. and A. Hajimiri, "Concurrent multiband low-noise amplifiers theory, design and applications," IEEE Trans. Microw. Theory Tech., Vol. 50, No. 1, 288-301, Jan. 2002.
4. Tsai, L. C. and C. W. Hsue, "Dual-band bandpass filters using equal length coupled serial-shunted lines and Z-transform technique," IEEE Trans. Microw. Theory Tech., Vol. 52, No. 4, 1111-1117, Apr. 2004.
5. Kuo, J.-T. and H.-S. Cheng, "Design of quasi-elliptic function filters with a dual-passband response," IEEE Microw. Compon. Lett., Vol. 14, No. 10, 472-474, Oct. 2004.
6. Miyake, H., S. Kitazawa, T. Ishizaki, T. Yamada, and Y. Nagatomi, A miniaturized monolithic dual band filter using ceramic lamination technique for dual mode portable telephones , 1997 IEEE MTT-S Int. Microwave Symp. Dig., 789-792, 1997.
7. Kuo, J.-T., T.-H. Yeh, and C.-C. Yeh, "Design of Microstrip Bandpass Filters with a Dual-passband response," IEEE Trans. Microwave Theory and Tech., Vol. 53, No. 4, 1331-1337, Apr. 2005.
8. Chang, S.-F., J.-L. Chen, and S.-C. Chang, New dual-band bandpass ¯lters with step-impedance resonators in comb and hairpin structures , Asia-Paci¯c Microwave Conf., 793-796, 2003.
9. Quendo, C., E. Rius, and C. Person, An original topology of dual-band filter with transmission zeros, 2003 IEEE MTT-S Int. Microwave Symp. Dig., 1093-1096, 2003.
10. Guan, X., Z. Ma, P. Cai, Y. Kobayashi, T. Anada, and G. Hagiwara, "Synthesis of dual-band bandpass filters using successive frequency transformations and circuit conversions ," IEEE Microwave and Wireless Components Letters, Vol. 16, No. 3, Mar. 2006.
11. Garcia-Lamperez, A. and M. Salazar-Palmat, "Dual band filter with split-ring resonators," Microwave Symposium Digest, 2006. IEEE MTT-S International, 519-522, Jun. 2006.
12. Pendry, J. B., A. J. Holden, D. J. Robbins, and W. J. Stewart, "Magnetism from conductors and enhanced nonlinear phenomena," IEEE Trans. Microwave Theory Tech., Vol. 47, 2075-2084, 1999.
13. Marques, R., F. Martin, and M. Sorolla, Metamaterials with Negative Parameters, Theory, Design and Microwave Applications, John Wiley & Sons, Inc., New Jersey, 2008.
14. Hong, J.-S. and M. J. Lancaster, "Couplings of microstrip square open-loop resonators for cross-coupled planar microwave filters," IEEE Trans. Microwave Theory Tech., Vol. 44, 2099-2103, Dec. 1996.
15. Wang, X.-H., B.-Z. Wang, and K. J. Chen, "Compact broadband dual-band bandpass filters using slotted ground structures," Progress In Electromagnetics Research, Vol. 82, 151-166, 2008.
16. Wu, G.-L., W. Mu, X.-W. Dai, and Y.-C. Jiao, "Design of novel dual-band bandpass filter with microstrip meander-loop resonator and CSRR DGS," Progress In Electromagnetics Research, Vol. 78, 17-24, 2008.