A novel planar omnidirectional antenna

The planar printed antenna is an attractive type of antenna due to their low cost, conformability, and ease of manufacture. The dipole antenna printed on a dielectric substrate has been developed to suit the needs of various communication systems. The single dipole has an omnidirectional pattern in the H plane. Sometimes, in the application of mobile communication, indoor radio and wireless communication systems, an omnidirectional characteristic both in the E and H plane is needed. In this paper, a new structure of a planar dipole antenna and the feeding network are presented. Compared with the conventional planar antennas, the antenna we propose shows quite good 3D omnidirectivity and at the same time it inherits nearly all the excellent performance of normal planar antennas.