Omni-directional printed antenna array for MIMO application

A compact two-channel multiple input multiple output (MIMO) printed microstrip antenna array is proposed. In this work, an omni-directional monopole antenna array is design with five elements and then two numbers of similar arrays have been employed for MIMO application at 5.25 GHz. The antenna is composed of five rectangular shaped patch elements that cascade of antenna elements arranged alternately on the top and bottom surfaces of the substrate. The proposed two channel printed monopole array is designed to give a solution for a WLAN base station antenna. The antenna exhibits low crosses polarization, high gain and high isolation between the ports. The antenna with compact structure based on the design has a peak gain of 11.80 dBi and cross polarization less than -15.5 dB at the designed frequency. The port isolation has been successfully optimized to a value of -25dB by adjusting the distances between two arrays. Simulated results show that the proposed antenna offers good impedance matching, high gain and a band width of 150 MHz. The simulation results of reflection coefficient, port isolation and the radiation pattern are presented and discussed.