This paper proposes the design and implementation of a circular triangle fractal antenna for portable ultra-wideband (UWB) communication applications with band rejection at WLAN band. The presented antenna is made with iterative generation of a circular triangle shaped elements arranged in circular fashion with self-similarity and periodicity property with coplanar waveguide feed. The overall dimensions of the antenna are 28× 27 x 1.6 mm3. The fractal resonating plane and ground plane dimensions of the proposed antenna are optimized to obtain a resonance bandwidth of 2.39-12.28 GHz which corresponds to fractional bandwidth of 134.8% with notch band from 5.45 to 6.27 GHz to mitigate the problem of interference from WLAN. The peak gain detected is 11.16 dBi. The proposed prototype was fabricated on a 1.6 mm thick FR4 material with the relative permittivity of 4.4, and the sample was tested. The experimental results are in close agreement with the simulated ones. The time domain analysis indicates that the proposed antenna is not dispersive. The antenna radiates in a virtually omnidirectional pattern. Due to these merits, this proposed antenna can be used in UWB applications.
2. Oppermann, I., M. Hämäläinen, and J. Iinatti, UWB: Theory and Applications, John Wiley & Sons, 2004.
doi:10.2528/PIERC12052310
3. Karmakar, A., S. Verma, M. Pal, and R. Ghatak, "An ultra-wideband monopole antenna with multiple fractal slots with dual band rejection characteristics," Progress In Electromagnetics Research C, Vol. 31, 185-197, 2012.
doi:10.1002/mop.30204
4. Rani, B. R. and S. K. Pandey, "A parasitic hexagonal patch antenna surrounded by same shaped slot for WLAN, UWB applications with notch at vanet frequency band," Microw. Opt. Technol. Lett., Vol. 58, No. 12, 2996-3000, 2016.
doi:10.2528/PIERC20040701
5. Parchin, N. O., H. J. Basherlou, and R. A. Abd-Alhameed, "UWB microstrip-fed slot antenna with improved bandwidth and dual notched bands using protruded parasitic strips," Progress In Electromagnetics Research C, Vol. 101, 261-273, 2020.
doi:10.1109/TAP.2009.2027727
6. Ryu, K. S. and A. A. Kishk, "UWB antenna with single or dual band-notches for lower WLAN band and upper WLAN band," IEEE Trans. Antennas Propag., Vol. 57, No. 12, 3942-3950, 2009.
doi:10.1002/mop.32111
7. Fertas, K., F. Ghanem, A. Azrar, and R. Aksas, "UWB antenna with sweeping dual notch based on metamaterial SRR fictive rotation," Microw. Opt. Technol. Lett., Vol. 62, No. 2, 956-963, 2020.
doi:10.2528/PIERL20012903
8. Sanmugasundaram, R., N. Somasundaram, and R. Rajkumar, "Ultrawideband notch antenna with EBG structures for WiMAX and satellite application," Progress In Electromagnetics Research, Vol. 91, 25-32, 2020.
9. Mandelbrot, B. B., Fractals. Form, Chance and Dimension, Freeman, 1977.
doi:10.1109/EIF.1997.605374
10. Cohen, N., "Fractal antenna applications in wireless telecommunications," Professional Program Proceedings. Electronic Industries Forum of New England, 43-49, 1997.
doi:10.1109/MAP.2003.1189650
11. Werner, D. H. and S. Ganguly, "An overview of fractal antenna engineering research," IEEE Antennas Propag Mag., Vol. 45, No. 1, 38-57, Mar. 2003.
12. Haji-Hashemi, M. R., M. Moradian, and H. Mirmohammad-Sadeghi, "Space-filling patch antennas with CPW feed," Prog. Electromagn. Res. S., Vol. 2, No. 1, 69-73, 2006.
13. Ramya, M. C. and B. R. Rani, "A compendious review on fractal antenna geometries in wireless communication," International Conference on Inventive Computation Technologies (ICICT), IEEE, 888-893, 2020.
14. Ramya, M. C. and B. R. Rani, "Fractal based ultra-wideband antenna design: A review," Planar Antennas: Design and Applications, P. K. Malik (ed.), 1st Edition, CRC press, 131-151, 2021.
doi:10.2528/PIERC11082801
15. Ghatak, R., A. Karmakar, and D. R. Poddar, "A circular shaped Sierpinski carpet fractal UWB monopole antenna with band rejection capability," Progress In Electromagnetics Research, Vol. 24, 221-234, 2011.
doi:10.1016/j.aeue.2012.08.007
16. Ghatak, R., A. Karmakar, and D. R. Poddar, "Hexagonal boundary Sierpinski carpet fractal shaped compact ultrawideband antenna with band rejection functionality," AEU - Int. J. Electron. Commun., Vol. 67, No. 3, 250-255, 2013.
doi:10.2528/PIERC13011607
17. Ghatak, R., B. Biswas, A. Karmakar, and D. Poddar, "A circular fractal UWB antenna based on Descartes circle theorem with band rejection capability," Progress In Electromagnetics Research C, Vol. 37, 235-248, 2013.
doi:10.1049/iet-map.2013.0235
18. Choukiker, Y. K. and S. K. Behera, "Modified Sierpinski square fractal antenna covering ultra-wide band application with band notch characteristics," IET Microw. Antennas Propag., Vol. 8, No. 7, 506-512, 2014.
doi:10.1002/mop.32304
19. Garg, R. K., M. V. Nair, S. Singhal, and R. Tomar, "A new type of compact ultra-wideband planar fractal antenna with WLAN band rejection," Microw. Opt. Technol. Lett., Vol. 62, No. 7, 2537-2545, 2020.
doi:10.1016/j.aeue.2017.06.017
20. Gupta, M. and V. Mathur, "Wheel shaped modified fractal antenna realization for wireless communications," AEU - Int. J. Electron. Commun., Vol. 79, 257-266, 2017.
doi:10.2528/PIERC18040605
21. Ali, T., B. K. Subhash, and R. C. Biradar, "A miniaturized decagonal Sierpinski UWB fractal antenna," Progress In Electromagnetics Research C, Vol. 84, 161-174, 2018.
22. Balanis, C. A., Antenna Theory: Analysis and Design, 4th Ed., John Wiley & Sons, 2016.
23. Ansoft Corp., HFSS, ver. 14.0, Pittsburgh, PA, USA [Online]. Available: http://www.ansys.com.