Using the Parasitic Element Method to Reduce the Mutual Coupling in the Design of (2x1) MIMO Triple-Band Antenna for 5G Wireless Transmission Application

This study presents the design and analysis of a compact (72x46) mm2 broad-band printed MIMO (2x1) antenna. The antenna is intended to operate at frequencies (15.5-22.5-29.5) GHz and is specifically developed for wireless power transmission in fifth-generation (5G) applications. The MIMO antenna is fabricated on an FR4 substrate with an electronic conductivity (E) of 4.4, a height of 1.6mm, and a tand value of 0.025. The patch is designed in the form of a circular ring consisting of two large circles engraved on the front side of the FR4 material, the first with a radius of 12.999 mm from which a small circle with a radius of 10 mm is cut, and its center is 3 mm away from the large circle on the y-axis. The parasitic technique was used in this antenna to reduce the mutual coupling between two ports, which consist of 6 rectangular pieces that are hollow from the, inside to prevent the transmission of the wave from the first port to the second and vice versa, which causes the loss of transmitted energy. The design and simulation results of this MIMO antenna were achieved using the Cognitive Simulation Technology (CST) Microwave Studio software package version 2024. The simulation revealed that the S-parameter for the 2-port is below -17 dB, and the mutual coupling for these ports is significantly low, measuring less than -50 dB.