Single-layer frequency selective dual-band reflectarray operating at 28 GHz and 39 GHz

Abstract

We report a single-layer frequency selective dual band reflectarray operated at 28 and 39 GHz simultaneously. The reflectarray consists of cross dipole and spiral elements aligned on the surface of a substrate and dual band frequency selective surfaces aligned on the rear side. We aligned the cross dipole and spiral elements that can control the reflection direction at 28 and 39 GHz aligned on the same plane of the substrate, resulting in a simultaneous dual-band control of the reflection direction up to ± 30° independently. Furthermore, the dual band reflectarray showed higher transmittance at frequencies except for the target frequencies, indicating the reflectarray function only at 28 and 39 GHz and does not interfere with the other communication bands.

Electronically Reconfigurable 100-GHz Band Reflectarray for Wireless Communication Based on Microfiber/Liquid Crystal Composite

“…The RA's RCS value is assessed through the comparison method, involving measuring the reflected power of a flat copper plate of identical size (20 mm × 20 mm) placed in the same location, serving as a reference. Notably, for a flat plate, the RCS value is equal to 4𝜋𝐴 2 𝜆 2 ⁄ , where A is the area of the plate [12]. Furthermore, spatial constraints exist in front of Tx and adjacent to the enclosure wall, limiting the measurement range to ±10°-±85°.…”

“…To manipulate the direction of the reflected wave, RAs are often designed with patterns of continuously varying sizes [2] or employ tunable elements such as ferroelectric [3], micro-electromechanical systems (MEMS) [4], and liquid crystal (LC) [5,6,7,8,9,10]. RAs using ferroelectrics and MEMS exhibit exceptionally rapid response times, typically on the order of μs.…”