A Coplanar Waveguide(CPW)-fed monopole loaded with Composite Right/Left Handed Transmission Line (CRLH-TL) unit cell is presented in this letter. Multiband is achieved due to the nonlinear dispersion relation of the CRLH-TL unit cell. The CRLH-TL unit cell supports a fundamental LH wave (phase advance) at lower frequencies and a RH wave (phase delay) at higher frequencies. By loading CRLH-TL unit cells with a conventional monopole, the resonant frequency of higher order mode can be decreased and zeroth-order mode or even negative-order mode can be achieved. As a result, the proposed antenna operates at 1.43 GHz, 2.58 GHz, 3.31 GHz and 4.4 GHz. Finally the modified antenna is fabricated and measured; measurements and EM simulations are in a good agreement that confirms the proposed theory.
2. Zhu, J., M. A. Antoniades, and G. V. Eleftheriades, "A compact tri-band monopole antenna with single-cell metamaterial loading," IEEE Trans. Antennas Propag., Vol. 58, No. 4, 1031-1038, Apr. 2010.
3. Niu, B.-J. and Q.-Y. Feng, "Bandwidth enhancement of CPW-fed antenna based on epsilon negative zeroth-order and first-order resonators," IEEE Antennas Wireless Propag. Lett., Vol. 12, 1125-1128, 2013.
4. Jin, P. and R. W. Ziolkowski, "Broadband, efficient, electrically small metamaterial-inspired antennas facilitated by active near-field resonant parasitic elements," IEEE Trans. Antennas Propag., Vol. 58, No. 2, 318-327, Feb. 2010.
5. AIbrahim, A., A. M. E. Safwat, and H. ElHennawy, "Triple-band microstrip-fed monopole antenna loaded with CRLH unit cell," IEEE Antennas Wireless Propag. Lett., Vol. 10, 1574-1550, 2011.
6. Taher, H., "High-performance low-pass filter using complementary square split ring resonators defected ground structure," ET Microw. Antennas Propag., Vol. 5, No. 7, 771-775, 2011.
7. Iizuk, H. and P. S. Hall, "Left-handed dipole antennas and their implementations," IEEE Trans. Antennas Propag., Vol. 55, No. 5, 1246-1253, May 2007.
8. Caloz, C. and T. Itoh, Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications, Wiley, New York, NY, USA, 2006.
9. Belenguer, A., A. L. Borja, and V. E. Boria, "Balanced dual composited right/left-handed microstrip line with modified complementary split-ring resonators," IEEE Antennas Wireless Propag. Lett., Vol. 12, 880-883, 2013.