Triangular patch resonator bandpass filters with tunable operation are developed to perform nicer filter properties of low passband insertion loss, transmission zeros and wide stopband. With tunable fractal-shaped defection acts as perturbation, filter operation frequency and operation band can be controlled, and the responses of undesired resonant modes are greatly weakened even suppressed. The new design can bring filters more operation without changing the dielectric substrate or patch size. The designed filters have outstanding advantages of single patch with compact size and without resonator coupling gaps, simple circuit topology, nicer performances, miniaturization and can be easily tuned for more applications. All these features are well popular for wireless communication systems.
2. Zhang, J., J.-Z. Gu, B. Cui, and X.-W. Sun, "Compact and harmonic suppression open-loop resonator bandpass filter with tri-section SIR," Progress In Electromagnetics Research, Vol. 69, 93-100, 2007.
3. Zhao, L.-P., X. Zhai, B. Wu, T. Su, W. Xue, and C.-H. Liang, "Novel design of dual-mode bandpass filter using rectangle structure," Progress In Electromagnetics Research B, Vol. 3, 131-141, 2008.
4. Xiao, J.-K., S.-P. Li, and Y. Li, "Novel planar bandpass filters using one single patch resonators with corner cuts," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 11, 1481-1493, 2006.
5. Xiao, J.-K. and Y. Li, "Novel compact microstrip square ring bandpass filters," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 13, 1817-1826, 2006.
6. Wang, Y.-X., B.-Z. Wang, and J. P. Wang, "A compact square loop dual-mode bandpass filter with wide stop-band," Progress In Electromagnetics Research, Vol. 77, 67-73, 2007.
7. Chen, Z.-X., X.-W. Dai, and C.-H. Liang, "Novel dual-mode dualband bandpass filter using double square-loop structure," Progress In Electromagnetics Research, Vol. 77, 409-416, 2007.
8. Helszajn, J. and D. S. James, "Planar triangular resonators with magnetic walls," IEEE Trans. Microwave Theoryand Techniques, Vol. 26, No. 2, 95-100, 1978.
9. Hong, J. S. and S. Li, "Theory and experiment of dual-mode microstrip triangular-patch resonators and filters," Theory and experiment of dual-mode microstrip triangular-patch resonators and filters, Vol. 52, No. 4, 1237-1243, 2004.
10. Hong, J. S., "Microstrip dual-mode band reject filter," IEEE MTT-S Digest, 945-948, 2005.
11. Zhao, L.-P., X.-W. Dai, Z.-X. Chen, and C.-H. Liang, "Novel design of dual-mode dual-band bandpass filter with triangular resonators," Progress In Electromagnetics Research, Vol. 77, 417-424, 2007.
12. Lugo, C. and J. Papapolymerou, "Bandpass filter design using a microstrip triangular loop resonator with dual-mode operation," IEEE Trans. Microwave and Wireless Components Letters, Vol. 15, No. 7, 475-477, 2005.
13. Xiao, J.-K., Q. Chu, and S. Zhang, "Novel microstrip triangular resonator bandpass filter with transmission zeros and wide bands using fractal-shaped defection ," Progress In Electromagnetics Research, Vol. 77, 343-356, 2007.
14. Khan, S. N., J. Hu, J. Xiong, and S. He, "Circular fractal monopole antenna for low VSWR UWB applications," Progress In Electromagnetics Research Letters, Vol. 1, 19-25, 2008.