Four-port rectangular monopole antenna for UWB-MIMO

Abstract

This paper proposes a four-port rectangular monopole antenna for ultra-wideband multipleinput multiple-output (UWB-MIMO) applications. The proposed antenna was designed by using step etching on the ground plane and arrow-shaped slot etching on a radiating patch to enhance bandwidth and improve performances. The homogeneous elements and angular variation techniques were applied to reduce mutual coupling between multiple antenna elements. The structural simulation technique used Computer Simulation Technology (CST) program to analyze the antenna characteristics such as reflection coefficient, group delay, mutual coupling, envelope correlation coefficient, and radiation patterns. The measured results were found to cover a frequency range of 3.1-10.6GHz for UWB communications. The envelope correlation coefficient for the MIMO system was obtained under 0.001 which is less than the specific parameters of UWB-MIMO antennas. The radiation pattern was bidirectional. Also, the efficiency of the four-port antenna was more than 85.70%.