Left-handed transmission line based on tunable interdigital capacitance and application to backfire-to-endfire leaky-wave antenna

In this paper, based on the interdigital capacitance, a kind of optimizing approach by tuning length of the interdigital lines respectively is presented. And the workload could be reduced greatly when this approach is applied to the left-handed transmission line(LH-TL) design. From the simulation results, it can be seen that the passband width of the LH-TL could be increased significantly. After that, a type of backfire-to-endfire leaky-wave antenna based on this new LH-TL has been studied. The radiation direction shifts from back to end with the increasing of frequency.