Vanadium oxide-based 16 × 16 reflectarray or FSS, reflect-transmitarray and FSS-based Cross-polarized wave absorber for future 6G applications

Abstract In this paper, a novel unit cell-based array is designed and analyzed using a VO 2 -based intelligent ground plane. The proposed array can be used as reflectarray or frequency selective surface (FSS), FSS based cross-polarized wave absorber, and reflective-transmittive surface. The intelligent ground plane is made up of a cross-shaped slot, and it is filled with a thin vanadium dioxide (VO 2 ) layer. The conductivity of the VO 2 material is temperature-sensitive and it is changed due to the applied external DC biasing. The tunability of VO 2 conductivity introduces the quad-function performance characteristics in a single array at 1–2 THz band. The first application of reflectarray is obtained by high DC (V 1 Volt) biasing, while the other three applications are achieved by low voltage V 2 (V 2 < V 1 ). A polarization rotating unit cell (PRUC) is designed to enhance the bandwidth and to obtain a wide 180° phase shift. This novel compact array saves the cost and area for THz applications. The array consists of 16 × 16 elements which is illuminated by a normal incidence of pyramidal horn antenna. The total volume of the array is 1600 × 1600 × 2100 μm 3 . The performance characteristics of the individual unit cell and array with and without intelligent ground plane are simulated in CST Microwave Studio.