In this article, a coplanar inverted-F antenna with an electronically controlled ground slot enabling reconfigurability is proposed. Initially a quarter wavelength coplanar inverted-F radiator is designed to operate at 900 MHz. To minimize its size, the radiator is folded to occupy an area of about 10 × 40 mm2. Next, a ground slot is introduced to excite another resonance at around 1850 MHz without affecting the 900 MHz operation. The slot is loaded with three pairs of PIN diode switches with simple biasing circuits to vary its resonant frequency. The proposed reconfigurable antenna is fabricated and experimentally tested. A good agreement is achieved between the simulated and measured return loss of the antenna showing the experimental impedance bandwidth covering GSM900, PCS1900 and UMTS2100 services. In these frequency bands, the antenna offers nearly omni-directional radiation patterns with measured peak gain between 1.4 dBi to 3.45 dBi.
2. Li, , H., , J. Xiong, Y. Yu, and S. He, "A simple compact recon¯gurable slot antenna with a very wide tuning range," IEEE Trans. Antennas and Propagation, Vol. 58, No. 11, 3725-3728, 2010..
3. Anagnostou, , D. E., A. A. Gheethan, and , "A coplanar recon¯gurable folded slot antenna without bias network for WLAN ," IEEE Antennas Wireless Propag. Lett., Vol. 8, 1057-1060, 2009.
4. Mak, A. C. K., C. R. Rowel, R. D. Murch, and C. L. Mak, "Recon¯gurable multiband antenna design for wireless communication devices," IEEE Trans. Antennas and Propagation, Vol. 55, No. 7, 1919-1928, 2007.
5. Lai, , M. L., , T. Y. Wu, J. C. Hsieh, C. H. Wang, and S. K. Jeng, "Design of reconfigurable antennas based on an L-shape slot and PIN diodes for compact wireless devices," IET Microwaves Antennas and Propag., Vol. 3, No. 1, 47-54, 2009.
6. Byun, , S. B., , J. A. Lee, J. H. Lim, and T. Y. Yun, "Reconfigurable ground-slotted patch antenna using PIN diode switching," ETRI Journal, Vol. 29, No. 6, 832-834, 2007.
7. Wu, , S. J. and T. G. Ma, "A wideband slotted bow-tie antenna with recon¯gurable CPW-to-slotline transition for pattern diversity," IEEE Trans. Antennas and Propagation, Vol. 56, No. 2, 327-334, 2008.
8. Kang, , W. S., , J. A. Park, and Y. J. Yoon, "Simple reconfigurable antenna with radiation pattern," Electronics Lett., Vol. 44, No. 3, 182-183, 2008.
9. Sarrazin, J., Y. , Mahe, S. Avrillon, and S. Toutain, "Pattern reconfigurable cubic antenna," IEEE Trans. Antennas and Propagation, Vol. 57, No. 2, 310-317, 2009.
10. Soliman, , E. A., W. De Raedt, and G. A. E. Vandenbosch, "Reconfigurable slot antenna for polarization diversity," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 7, 905-916, 2009.
11. Lai, , C.-H., , T.-Y. Han, and T.-R. Chen, "Circularly-polarized reconfigurable microstrip antenna," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 2--3, 195-201, 2009.
12. Lin, S.-Y., , Y.-C. Lin, and J.-Y. Lee, "T-strip FED patch antenna with reconfigurable polarization," Progress In Electromagnetics Research Letters, Vol. 15, 163-173, 2010.
13. Ali, M. T., M. N. Md Tan, T. B. A. Rahman, M. R. B. Kamarudin, M. F. Jamlos, and R. Sauleau, , "A novel reconfigurable planar antenna array (RPAA) with beam steering control," Progress In Electromagnetics Research B, Vol. 20, 125-146, 2010.
14. Kingsley, , N., D. E. Anagnostou, M. Tentzeris, and J. Papapolymerou, "RF MEMS sequentially-reconfigurable Sierpinski antenna," IEEE/ASME J. Microelectromech. Syst.,, Vol. 16, No. 5, 1185-1192, 2007.
15. Ramadan, , A., K. Y. Kabalan, A. El-Hajj, S. Khoury, and M. Al-Husseini, "A recon¯gurable U-koch microstrip antenna for wireless applications ," Progress In Electromagnetics Research, Vol. 93, 355-367, 2009.
16. Monti, , G., , R. De Paolis, and L. Tarricone, "Design of a 3-state recon¯gurable CRLH transmission line based on MEMS switches," Progress In Electromagnetics Research, Vol. 95, 283-297, 2009.
17. Karmakar, N. C., M. E. Bialkowski, and , "High performance L-band series and parallel switches using low-cost P-I-N diodes," Microw. Opt. Technol. Lett., Vol. 32, No. 5, 367-370, 2002.
18. Wong, , K.-L., Planar Antennas for Wireless Communications, Wiley, New York, 2003.
19. Razali, , A. R. and M. E. Bialkowski, "Coplanar inverted-F antenna with open-end ground slots for multiband operation," IEEE Antennas Wireless Propag. Lett., Vol. 8, 1029-1032, 2009.
20. Byndas, A., , R. Hossa, M. E. Bialkowski, and P. Kabacik, "Investigations into multi-band operation of single and multi-layer configurations of an inverted-F antenna," IEEE Antennas Propagation Magazine, Vol. 49, No. 4, 22-33, 2007.