Low Gain Ripple and DC-Grounded Slant-Polarized Formulation With 360° Broadbeam Coverage

Abstract

In this paper, a new slant-polarized slot antenna configuration is presented for direction finding and base station applications. The proposed antenna comprises enhanced size coaxial cables, slots, and feeding assemblies. The slant polarization is achieved by four angled slots etched around the outer cylinder of the oversized coaxial cable. An internal compact axis-symmetric feeding network connects primary apertures to form the omnidirectional antenna. Simulations and measurements demonstrate that the antenna maintains an omnidirectional pattern from 2.5 GHz to 2.8 GHz, having 11.3% bandwidth (measured return loss <; -10 dB) and gain ripple of ±0.2 dB in the azimuth plane, which leads to the stable operational coverage. Another benefit of this structure is its polarization purity. The cross-polarization levels are below -14dB over the whole bandwidth. Move over; it is ruggedized DC short, self-supporting, and surface-mountable structure. Furthermore, compact and conformal shape reduces aerodynamic drag and makes this antenna a potential candidate for mounting vehicle systems too.

Keywords

• Omnidirectional
• gain ripple
• slant polarization
• dc ground
• rugged