Development of a Dual-Polarized Direction-Variable Liquid-Crystal Meta-Surface Reflector for Intelligent Reflecting Surface

Intelligent reflecting surfaces (IRSs) have been attracting attention as a solution to coverage hole problems in millimeter-wave communication areas. They are considered be one of the key technologies next-generation mobile systems. Since polarized multiple-input-multiple-output (MIMO) is utilized systems deliver high-speed data transmission, an IRS also required applied for MIMO and reflect signals wide angle range. To realize MIMO, signal each polarization same direction with high isolation. In addition, control reflection phase over recent research, many proposals related development IRSs proposed. However, since configuration conventional diodes controls characteristics by controlling electric length or shape element, it becomes asymmetrical difficult apply MIMO. solve this problem, paper, we propose new design dual-polarized liquid-crystal-based 28 GHz proposed thickness substrate, can without changing element. By optimizing achieve 260 degrees both vertical horizontal polarizations. The range ±60 isolation more than 20 dB. main contributions paper 1) proposal liquid crystal MIMO; 2) method liquid-crystal using unit cell analysis; 3) verification through electromagnetic field 4) IRS; 5) experimental anechoic chamber, 6) derivation channel capacity IRS.