Balanced Dual Composite Right/Left-Handed Microstrip Line With Modified Complementary Split-Ring Resonators

This letter presents a dual composite right/left-handed microstrip line loaded with modified complementary split-ring resonators. In this particular case, the well-known resonant particle employed has been capacitively loaded in order to obtain a balanced frequency response. The inclusion of this capacitive element has two main effects. On the one hand, the right-and left-handed bands are interchanged; on the other hand, the possibility to control the position of the right-handed band, while maintaining the left-handed one unaltered. Consequently, it is relatively simple to design balanced transmission lines with improved bandwidth and reconfigurable properties. In addition, the equivalent circuit that describes the electromagnetic behavior of the structure has been obtained. Finally, a prototype has been fabricated and measured to confirm experimentally the validity of the proposed design.