Dual-Band and Dual-Polarized Reflectarray for Intelligent Reflecting Surface Applications in Millimeter-Wave 5G

In this work, a dual-band and dual-polarized reflectarray is proposed for non-tunable Intelligent Reflecting Surfaces (IRS) in millimeter-wave 5G. The reflectarray unit-cell has a dual-layer configuration, where the printed elements on each layer are designed to provide the required phase shifts at a different operating frequency (lower layer elements for 28 GHz and upper layer elements for 39 GHz). A 20 cm x 20 cm reflectarray panel has been designed to produce a collimated beam in dual-linear polarization at the 28 GHz and 39 GHz bands simultaneously. The proposed concept can be used to design passive IRS panels (without tunability) with dual-band operation, which can be used to improve coverage of dead zones or avoid obstacles that block direct communication links in millimeter-wave 5G networks.