Optimizing Patch and Ground Electrodes Design for Intelligent Reflecting Surface Based on Liquid Crystal Display Technology

The use of intelligent reflecting surfaces (IRSs) has garnered attention for enhancing wireless communications through millimeter-wave frequencies. This paper examines the electrode design of the unit cell for the IRS employing liquid crystal display technology. Numerical studies revealed that the bias lines connected to patch electrodes should match the length of the patch electrodes and that a metal layer should underlie the ground electrode. Furthermore, we prototyped an IRS with thin film transistors, achieving a reflection amplitude of - 3.8 dB and a maximum phase change of 281 degrees. These findings provide insights into enhancing the performance of IRS in mobile communication systems.