Broadband omnidirectional metal-plate monopole antenna

A novel broad-band omnidirectional metal-plate monopole antenna is presented. The proposed antenna is a step-shaped metal-plate monopole, which is easily fabricated from bending a metal plate (a 0.2 mm thick brass sheet used in this study). The proposed antenna shows improved omnidirectional radiation for frequencies across a very wide operating bandwidth (frequency ratio about 1:3), compared to a corresponding planar monopole antenna. Details of the proposed antenna design are described, and the experimental performance of some prototypes is studied.