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 TE 01 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.