Leaky characteristics of a new omni-directional periodic rod antenna gloved with A LHM shell

A new omni-directional leaky-wave antenna is proposed in the paper, which is consisted of circular rod corrugations gloved with a left-handed material (LHM) shell. The leaky characteristics of the new antenna are analyzed by improved perturbation method. The electromagnetic fields are described in terms of a radial transmission-line network, which tremendously simplifies the analysis procedure with good calculation accuracy and brings considerable physical insight into the overall behavior of the dielectric grating antenna. The case where the n=-1 space harmonic of TE₀₁ mode radiating into the space is carefully investigated, it is demonstrated that the gloved cylindrical LHM shell greatly enhances the leaky strength of the antenna. As a result, the dimension of the antenna could be largely reduced keeping the radiation efficiency unchanged, which is of practical significance for some applications.