A novel microstrip fed ultra-wideband (UWB) antenna with different band rejection techniques is presented in this paper. The antenna consists of a maple-leaf shaped radiator fed by a microstrip line with a finite ground plane on the other side of the substrate. The size of the UWB antenna is 30.5 × 35.5 mm2 which is only about 0.3 × 0.35 λ2 at 3 GHz. The calculated impedance bandwidth of the proposed antenna ranges from 3 GHz to 14 GHz with relatively stable radiation patterns. Two different techniques have been implemented to achieve band-notch characteristic in the 5.0-6.0 GHz WLAN frequency band. The first one uses an H-shaped slot cut away from the radiating patch while the other one uses two rectangular slits in the ground plane creating defected ground structure (DGS).
2. Zhao, Y., J. Xu, and K. Yin, "A minature coplanar waveguide-fed ultra-wideband antenna," Microwave and Millimeter Wave Technology, ICMMT 2008, 2008.
3. Zhang, J.-P., Y.-S. Xu, and W.-D. Wang, "Microstrip-fed semi-elliptical dipole antennas for ultrawideband communications," IEEE Trans. Antennas Propag., Vol. 56, 241-244, 2008.
4. Abbosh, A. and M. Bialkowski, "Design of ultra wideband planar monopole antennas of circular and elliptical shape," IEEE Trans. Antennas Propag., Vol. 56, 17-23, 2008.
5. Ahmed, O. and A. Sebak, "A printed monopole antenna with two steps and a circular slot for UWB applications," IEEE Antennas Wireless Propag. Lett., Vol. 7, 411-413, 2008.
6. Hsu, C.-H., "Planar multilateral disc monopole antenna for UWB application," Microwave Opt. Technol. Lett., Vol. 49, 1101-1103, 2007.
7. Liang, J., C. C. Chiau, X. Chen, and C. G. Parini, "Study of a printed circular disc monopole antenna for UWB systems," IEEE Trans. Antennas Propag., Vol. 53, 3500-3504, 2005.
8. Zhao, Y.-L., Y.-C. Jiao, G. Zhao, L. Zhang, Y. Song, and Z.-B. Wong, "Compact planar monopole UWB antenna with band-notched characteristic," Microwave Opt. Technol. Lett., Vol. 50, 2656-2658, 2008.
9. Huang, C.-Y., S.-A. Huang, and C.-F. Yang, "Band-notched ultra-wideband circular slot antenna with inverted C-shaped parasitic strip," Electron. Lett., Vol. 44, 891-892, 2008.
10. Hong, C.-Y., C.-W. Ling, I.-Y. Tarn, and S.-J. Chung, "Design of a planar ultrawideband antenna with a new band-notch structure," IEEE Trans. Antennas Propag., Vol. 55, 3391-3397, 2007.
11. Naghshvarian-Jahromi, M., "Compact UWB bandnotch antenna with transmission-linefed," Progress In Electromagnetics Research B, Vol. 3, 283-293, 2008.
12., HFSS, v10, Ansoft Corp., 2007.
13., CST Microwave Studio, ver. 2008, Computer Simulation Technology, Framingham, MA, 2008.
14. Bird, T. S., "Definition and misuse of return loss," IEEE Antennas and Propagation Magazine, Vol. 51, No. 2, 166-167, April 2009.