The electromagnetic characteristics of two-dimensional composite right/left-handed transmission lines (2D CRLH TLs) were investigated for the normal incidence of plane waves. The measured characteristic impedance and reflection phases exhibited resonant high impedance properties (equivalent to zero reflection phase) at a frequency within the left-handed mode for one-dimensional CRLH TL. An equivalent circuit was proposed to explain the measured characteristics. The relationship between the resonant frequency and the circuit parameters for 2D CRLH TLs was clarified by deriving an approximate equation for the resonant frequency. The surface-wave transmission characteristics for the 2D CRLH TLs were compared with those for a mushroom structure.
2. Pendry, J. B., A. J. Holden, D. J. Robbins, and W. J. Stewart, "Magnetism from conductors and enhanced nonlinear phenomena," IEEE Transactions on Microwave Theory and Technology, Vol. 47, No. 11, 2075-2084, 1999.
3. Smith, D. R., W. J. Padilla, D. C. Vier, S. C. Nemat-Nasser, and S. Schultz, "Composite medium with simultaneously negative permeability and permittivity," Physical Review Letters, Vol. 84, No. 18, 4184-4187, 2000.
4. Shelby, R. A., D. R. Smith, and S. Schultz, "Experimental verificationof a negative index of refraction," Science, Vol. 292, 77-79, 2001.
5. Eleftheriades, G. V., A. K. Iyer, and P. C. Kremer, "Planar negative refractive index media using periodically L-C loaded transmission lines," IEEE Transactions on Microwave Theory and Technology, Vol. 50, No. 12, 2702-2712, 2002.
6. Liu, L., C. Caloz, and T. Itoh, "Dominant mode leaky-wave antenna with backfire-to-endfire scanning capability," Electronics Letters, Vol. 38, No. 23, 1414-1416, 2002.
7. Caloz, C., A. Sanada, and T. Itoh, "A novel composite right-/left-handed coupled-line directional coupler with arbitrary coupling leveland broad bandwidth," IEEE Transactions on Microwave Theory and Technology, Vol. 52, No. 3, 980-992, 2004.
8. Lai, A., C. Caloz, and T. Itoh, "Composite right/left-handed transmission line metamaterials," IEEE Microwave Magazine, 34-50, Sep. 2004.
9. Sanada, A., C. Caloz, and T. Itoh, "Planar distributed structures with negative refractive index," IEEE Transactions on Microwave Theory and Technology, Vol. 52, No. 4, 1252-1263, 2004.
10. Kokkinos, T., C. D. Sarris, and G. V. Eleftheriades, "Periodic finite-difference time-domain analysis of loaded transmission-line negative-refractive-index metamaterials," IEEE Transactions on Microwave Theory and Technology, Vol. 53, No. 4, 1488-1495, 2005.
11. Sievenpiper, D., L. Zhang, R. F. Jimenez Broas, N. G. Alexopolous, and E. Yablonovitch, "Highimpedance electromagnetic surfaces with a forbidden frequency band," IEEE Transactions on Microwave Theory and Technology, Vol. 47, No. 11, 2059-2074, 1999.
12. Chandrasekaran, K. T., M. F. Karim, Nasimuddin, and A. Alphones, "CRLH structure-based highimpedance surface for performance enhancement of planar antennas," IET Microwaves, Antennas & Propagation, Vol. 11, No. 6, 818-826, 2017.
13. Iwamoto, S., A. Sanada, and H. Kubo, "Experimental investigation of reflection characteristics of a high-impedance surface by 2D balanced CRLH metamaterials without a forbidden frequency band," Proceedings of Asia-Pacific Microwave Conference, 1-4, 2007.
14. Rahman, M. and M. A. Stuchly, "Transmission line-periodic circuit representation of planar microwave photonic bandgap structures," Microwave and Optical Technology Letters, Vol. 30, No. 1, 15-19, 2001.
15. Gupta, K. C., R. Garg, I. Bahl, and P. Bhartia, Microstrip Lines and Slotlines, 2nd Edition, Artech House, Norwood, MA, 1996.
16., , http://www.keysight.com/upload/cmc upload/All/FreeSpaceSeminarRev2.pdf.
17. Mosallaei, H. and K. Sarabandi, "Antenna miniaturization and bandwidth enhancement using a reactive impedance substrate," IEEE Transactions on Antennas and Propagation, Vol. 52, No. 9, 2403-2414, 2004.