A novel dual-band annular ring slot antenna is investigated. The antenna consists of a center-fed circular microstrip patch antenna with a coupled annular ring. And it is shorted concentrically with a set of conductive vias. By adjusting the parameters of the antenna, the dual resonant frequencies for two modes (TM01 and TM02 modes) are achieved. The antenna is fabricated and tested. Results show that the proposed antenna with height of 0.0217λ0 can provide gains of 3.01 dBi at 2.6 GHz (the receiving frequency) and 5.74 dBi at 2.95 GHz (the transmitting frequency). Good agreement between the measurement and simulation for the return loss and radiation patterns is achieved. The proposed antenna has dual-band characteristics, simple structure, low profile, and omni-directional azimuth radiation pattern. It is suitable for aircraft both receiving and transmitting signals and frequency division duplex (FDD) applications.
2. Chen, J.-S., "Multi-frequency characteristics of annual-ring slot antennas," Microwave and Optical Technology Letters, Vol. 38, 506-511, 2003.
3. Sabri, H. and Z. Atlasbaf, "Two novel compact triple-band microstrip annular-ring slot antenna for PCS-1900 and WLAN applications," Progress In Electromagnetics Research Letters, Vol. 5, 87-98, 2008.
4. Chen, Q., H.-L. Zheng, J.-H. Hu, and S.-G. Jiang, "Design of CPW-fed dual-band circularly-polarized annular slot antenna with two perturbation strips," Progress In Electromagnetics Research C, Vol. 28, 195-207, 2012.
5. Liu, J.-C., B.-H. Zeng, C.-Y. Wu, and D.-C. Chang, "Double-ring slot antenna with tree-shaped coupling strip for WLAN 2.4/5-GHz dual-band applications," Microwave and Optical Technology Letters, Vol. 47, 347-349, 2005.
6. Bao, X.-L. and M.-J. Ammann, "Compact concentric annular-ring patch antenna for triple-frequency operation," Electronics Letters, Vol. 42, 1129-1130, 2006.
7. Batchelor, J.-C. and R.-J. Langley, "Microstrip annular ring slot antennas for mobile applications," Electronics Letters, Vol. 32, 1635-1636, 1996.
8. Chen, C. L. and N. G. Alexopoulos, "Triplate-fed arbitrarily-shaped annular ring slot antennas," IEEE Antennas and Propagation Society International Symposium, Vol. 4, 2070-2072, 2005.
9. Chen, J.-S. and H.-D. Chen, "Dual-band characteristics of annular-ring slot antenna with circular back-patch," Electronics Letters, Vol. 39, 487-488, 2003.
10. Nikolaou, S. and R. Bairavasubramanian, "Pattern and frequency reconfigurable annular slot antenna using PIN diodes," IEEE Transactions on Antennas and Propagation, Vol. 54, 439-448, 2006.
11. Sze, J.-Y., C.-G. Hsu, and S.-C. Hsu, "Design of a compact dual-band annular-ring slot antenna," IEEE Antennas and Wireless Propagation Letters, Vol. 6, 423-426, 2007.
12. Chiang, M.-J., T.-F. Hung, J.-Y. Sze, and S.-S. Bor, "Miniaturized dual-band CPW-fed annular slot antenna design with arc-shaped tuning stub," IEEE Transactions on Antennas and Propagation, Vol. 58, 3710-3715, 2010.
13. Sze, J.-Y., T.-H. Hu, and T.-J. Chen, "Compact dual-band annular-ring slot antenna with meandered grounded strip," rogress In Electromagnetics Research, Vol. 95, 299-308, 2009.
14. Lee, J. Y., T. S. Horng, and N. G. Alexopoulos, "Analysis of cavity-backed aperture and antennas with a dielectric overlay," IEEE Transactions on Antennas and Propagation, Vol. 42, 1556-1562, 1994.
15. Liu, H. C., T. S. Horng, and N. G. Alexopoulos, "Radiation of printed antennas with co-planar waveguide feed," IEEE Transactions on Antennas and Propagation, Vol. 43, 1513-1548, 1995.
16. Chen, C. L., W. E. McKinzie, and N. G. Alexopoulos, "Stripline-fed arbitrarily shaped printed-aperture antennas," IEEE Transactions on Antennas and Propagation, Vol. 45, 1186-1198, 1997.
17. Chen, C. and N. G. Alexopoulos, "Modeling microstrip line fed slot antennas with arbitrary shape," Electromagnetics, Vol. 15, 567-586, 1995.
18. Asem, A.-Z., F. Yang, and A. Kishk, "A broadband center-fed circular patch-ring antenna with a monopole like radiation pattern," IEEE Transactions on Antennas and Propagation, Vol. 57, 789-792, 2009.
19. Boutayeb, H. and T. A.Denidni, "Gain enhancement of a microstrip patch antenna using a cylindrical electromagnetic crystal substrate," IEEE Transactions on Antennas and Propagation, Vol. 55, 3140-3145, 2007.
20. Garg, R., P. Bhartia, I. Bahl, and A. Ittipiboon, Microstrip Antenna Design Handbook, Artech House, Norwood, MA, 2001.