Design of a birdcage-like antenna for collinear arrays

In this paper, an antenna solution for collinear arrays working in the UHF band is presented. It consists in a cylindrical dipole with vertical slots on its surface, assuming a birdcage shape. The antenna belongs to the category of folded dipoles and it can be suitable for air traffic control (ATC) applications. This antenna relates to a collinear antenna structure and, more precisely, to a vertical stacked array antenna. It provides omnidirectional radiation patterns and a good isolation between array elements. Two prototypes were manufactured and analyzed. Reflection coefficient and mutual coupling between two adjacent elements are shown. © 2011 IEEE.