This paper presents a realization of composite right/left handed transmission lines using coupled microstrip lines. This structure exploits the advantages of the microstrip lines, while increases the coupling by a floating conductor at the ground plane. The performance of this composite right/left-handed line is demonstrated by both simulated and measured results, and they show good agreement. The designed line has broad bandwidth with low losses and small size. A novel dominant mode leaky wave antenna design, using the previous structure, is presented with backward to forward scanning capability.
2. Lai, A., T. Itoh, and C. Caloz, "Composite right/left-handed transmission line metamaterials," IEEE Microwave Magazine, 34-50, Sep. 2004.
3. Abdelaziz, A. F., T. M. Abuelfadl, and O. L. Elsayed, "Realization of composite right/left-handed transmission line using coupled lines," Progress In Electromagnetics Research, Vol. 92, 299-315, 2009.
4. Abdelaziz, A. F., T. M. Abuelfadl, and O. L. Elsayed, "Realization of composite right/left-handed transmission line using broadside coupled coplanar waveguides," IEEE Inter. Symposium on Antennas and Propagation, APS, 2009.
5. Malherbe, J. A. G. and I. E. Losch, "Directional couplers using semireentrant coupled lines," Microwave Journal, 121-128, Nov. 1987.
6. Masot, F., F. Medina, and M. Horno, "Analysis and experimental validation of a type of three-microstrip directional coupler," IEEE Transactions on Microwave Theory and Techniques, Vol. 42, No. 9, 1624-1631, Sep. 1994.
7. Velazquez-Ahumada, M., J. Martel, and F. Medina, "Parallel coupled microstrip lters with oating ground-plane conductor for spurious-band suppression," IEEE Transactions on Microwave Theory and Techniques, Vol. 53, No. 5, 1823-1828, May 2005.
8. Liu, L., C. Caloz, and T. Itoh, "Dominant mode (DM) leaky-wave antenna with backre-to-endre scanning capability," Electron.Lett., Vol. 38, No. 23, 1414-1416, Nov. 2002.
9. Jones, E. M. T. and J. T. Bolljahn, "Coupled-strip-transmission-line lters and directional couplers," IRE Transactions on Microwave Theory and Techniques, 75-81, Apr. 1956.