Analysis of Planar Distributed Two-dimensional(2-D) Left-handed (LH) Structures

In this paper, a new approach is proposed to analyze planar distributed 2-D LH structures. The 4-port S parameters of the unit cell combined with the Bloch-Floquet theory are used to determine the dispersion relations and Bloch impedance. The LH and RH frequency bands are identified by the signs of the real parts of the wave number and the Bloch impedance. As an example, a capacitance-enhanced LH structure is designed and analyzed with the new approach. To demonstrate its effectiveness, FDTD simulation is also performed to illustrate the backward wave propagation in the periodic structure with infinite arrays in LH frequency band.