A dual wideband CPW-fed slotted Koch snowflake fractal monopole, which is suitable for WLAN/WiMAX applications, is presented. The proposed antenna has been analyzed and designed with Ansoft HFSSTM v.11. Then an experimental prototype is fabricated and measured. It is compact with a total size of 41.5 mm × 27 mm × 1 mm (L×W×T). Results of simulation and measurement indicate that the proposed fractal monopole with a U-shaped slot has dual impedance bandwidths 2.35-4.25 GHz and 4.8-5.95 GHz, which covers WLAN bands (2.4/5.2/5.8GHz) and the WiMAX bands (2.5/3.5/5.5 GHz) respectively. In addition, good radiation performances such as omnidirectional and doughnut-shaped directivity and goodish gain over the operating bands have been obtained.
2. Lizzi, , L. , G. Oliveri, and , "Hybrid design of a fractal-shaped GSM/UMTS antenna," Journal of Electromagnetic Waves and Applications, Vol. 24, No. 5--6, 707-719, 2010.
3. Viani, , F., , M. Salucci, F. Robol, G. Oliveri, and A. Massa, , "Design of a UHF RFID/GPS fractal antenna for logistics management," Progress In Electromagnetics Research, Vol. 26, No. 4, 480-492, 2012.
4. Vinoy, , K. J., "Fractal shaped antenna elements for wide and multi-band wireless applications," Ph.D. Dissertation, , 2002..
5. Romeu, , J. , Y. Rahmat-Samii, and , "Fractal FSS: A novel multiband frequency selective surface," IEEE Trans. Antennas Propagat. , Vol. 48, 713-719, 2000.
6. Puente, , C. , R. Pous, and , "Fractal design of multiband and low side-lobearrays," IEEE Trans. Antennas Propagat., Vol. 44, No. 5, 730-739, , 1996.
7. Anguera, J., , C. Puente, C. Borja, and J. Soler, "Fractal-shaped antennas: A review," Wiley Encyclopedia of RF and Microwave Engineering, K. Chang, Ed., Vol. 2, 1620-1635, 2005.
8. Gianvittorio, , J., , "Fractal antennas: Design, characterization and applications," Ph.D. Dissertation, Department of Electrical Engineering, University of California at Los Angeles, Los Angeles, 2000.
9. Werner, , D. H., , R. L. Haupt, and P. L. Werner, , "Fractal antenna engineering: The theory and design of fractal antenna arrays," IEEE Antennas Propagat. Mag., Vol. 41, No. 5, 37-58, 1999.
10. Baliarda, , C. P., J. Romeu, and A. Cardama, , "The Koch monopole: A small fractal antenna," IEEE Trans. Antennas Propagat., Vol. 48, No. 11, 1773-1781, , 2000.
11. Puente, , C., , J. Romeu, R. Pous, J. Ramis, and A. Hijazo, , "Small but long Koch fractal monopole," Inst. Elect. Eng. Electron. Lett., Vol. 34, No. 1, 9-10, 1998.
12. Borja, , C. , J. Romeu, and , "On the behavior of Koch island fractal boundary microstrip patch antenna," IEEE Trans. Antennas Propagat., Vol. 51, No. 6, , 2003.
13. Cohen, , N. , R. G. Hohlfeld, and , "Fractal loops and the small loop approximation," Commun. Quart., 77-81, 1996.
14. Cohen, , N., , "Fractal and shaped dipoles," Commun. Quart.,, 25-36, 1996..
15. Anagnostou, , D., , M. T. Chryssomallis, J. C. Lyke, and C. G. Christodoulou, "A CPW Koch dipole slot antenna," Proc. IEEE Topical Conf. Wireless Commun. Technol., No. 337, 15-17, 2003..
16. Sundaram, , A., M. Maddela, and R. Ramadoss, "Koch-fractal folded-slot antenna characteristics," IEEE Antennas and Wireless Propagation Letters, Vol. 6, 219-222, , 2007.
17. Krishna, , D. D., , M. Gopikrishna, C. K. Anandan, P. Mohanan and K. Vasudevan, "CPW-fed Koch fractal slot antenna for WLAN/WiMAX applications," IEEE Antennas and Wireless Propagation Letters, Vol. 7, , 389-392, 2008.