A planar dual-band semicircle shaped antenna for multi-input multi-output (MIMO) systems is introduced. The antenna was studied experimentally regarding bandwidth and radiation patterns. The measured -10 dB return loss bandwidth is from 2.27 to 2.53 GHz and 5.03 to 5.58 GHz, covering all the 2.4/5.2 GHz WLAN bands. Details of the antenna design, simulated and measured results on the return loss and the E- and H-plane radiation patterns of the proposed antenna are presented. The multi-feed 4-elements planar array is simulated using the commercially available software Ansoft HFSS and fabricated that are verified by good agreement between simulated and measured results. The enhanced performance is obtained by placing antennas uniquely to suppress mutual coupling and utilizing supplemental structure to miniaturize the size of the antennas.
2. Foschini, G. J. and M. J. Gans, "On limits of wireless communications in a fading environment when using multiple antennas," Wireless Personal Commun., Vol. 6, 311-335, 1998.
3. Chung, K. and J. H. Yoon, "Integrated MIMO antenna with high isolation characteristic," Electron. Lett., Vol. 43, 199-201, 2007.
4. Gao, Y., C. C. Chiau, X. Chen, and C. G. Parini, Modified PIFA and its array for MIMO terminals, Microwave Antenna. Propagat. IEE Proc., Vol. 152, 225-259, 2005.
5. Kuo, Y.-L. and K.-L.Wong, "Printed double-T monopole antenna for 2.4/5.2 GHz dual-band WLAN operations," IEEE Trans. Antennas Propagat., Vol. 51, 2187-2192, 2003.
6. Lee, B. M. and Y. J. Yoon, A dual fed and a dual frequency slots-loaded triangular microstrip antenna, IEEE Antenna and Propagation Society Int. Symp., No. 3, 1600-1603, 2000.
7. Maci, S., G. B. Gentill, P. Piazzesi, and C. Salvador, Dual-band slotloaded patch antenna, IEE Proc., Microw. Antennas Propag., Vol. 142, No. 3, 225-232, 1995.
8. Fang, S.-T., S.-H. Yeh, and K.-L. Wong, Planar inverted-F antennas for GSM/DCS mobile phones and dual ISM-band applications, IEEE Antenna and Propagation Society Int. Symp., Vol. 4, 524-527, 2002.
9. Cho, Y. J., Y. S. Shin, and S. O. Park, "Internal PIFA for 2.4/5 GHz WLAN applications," Electron. Lett., Vol. 42, No. 1, 8-10, 2006.
10. Chen, J. S., "Dual-frequency annular-ring slot antennas fed by CPW feed and microstrip line feed," IEEE Trans. Antennas Propag., Vol. 53, No. 1, 569-573, 2005.
11. Rhee, S. and G. Yun, "CPW fed slot antenna for triple-frequency band operation," Electron. Lett., Vol. 42, No. 17, 952-953, 2006.
12. Mallahzadeh, A. R., S. Eshaghi, and A. Alipour, "Design of an E-shaped MIMO antenna using IWO algorithm for wireless application at 5.8 GHz," Progress In Electromagnetics Research, Vol. 90, 187-203, 2009.
13. Min, K.-S., M.-S. Kim, C.-K. Park, and M. D. Vu, "Design for PCS antenna based on WiBro-MIMO," Progress In Electromagnetics Research Letters, Vol. 1, 77-83, 2008.
14. Krairiksh, M., P. Keowsawat, C. Phongcharoenpanich, and S. Kosulvit, "Two-probe excited circular ring antenna for MIMO application," Progress In Electromagnetics Research, Vol. 97, 417-431, 2009.