Design of a Novel Low-Cost High-Gain Dual-Polarized Antenna by Suspended Cylinder and Shorting Strips

Abstract

In this paper, a novel low-cost, high gain dual-polarized antenna design with a suspended cylinder and a ground connected cylinder geometry is proposed. The design structure of the antenna is simple and fabricated with two cylinders, two shorting strips, and a circular ground plane. All these components are easily fabricated from a copper sheet of thickness 0.4 mm, and the antenna is fed by two coaxial probes at the orthogonal planes on the circumference of the cylinders. A prototype is designed, fabricated and measured. The measured results show that the prototype has −10 dB impedance bandwidth of 34.37% at port 1 & 34.21% at port 2. Broadside gain from port 1 is 10.2-10.4 dBi & port 2 is 10.25-10.52 dBi, which indicates that the antenna has flat gain over the impedance bandwidth, and isolation between the ports is more than 15 dB from 2.65-3.6 GHz and more than 20 dB from 2.75-3.55 GHz. The isolation of the proposed antenna is improved by shorting the suspended cylinder to the ground plane by two shorting strips. The resonance frequency and isolation peak are simultaneously tunable with varying the width of the shorting strips. The parameters of the antenna are optimized by using HFSS, and good agreement between the simulated and measured results is obtained. The proposed dual polarized antenna can be used for base station applications such as LTE (Long Term Evolution) and WiMAX (Worldwide Interoperability for Microwave Access).