Manually reconfigurable reflecting surface (MRRS) by detached rotatable unit cells for 5G FR2 radio coverage at low-cost fabrication

A manually reconfigurable reflecting surface (MRRS) formed by detached rotatable unit cells is proposed to enhance the signal strengths in 5G FR2 radio coverage. The forming unit cell is a conductor-backed circular-patch-based element implemented with two anti-symmetric arms manually extendable to adjust the relative reflection phases. The proposed MRRS is structured in a two-substrate configuration on a ground plane. The first dielectric substrate accommodates all identical and detachable elements manually rotated to reconfigure the MRRS's reflection phases. In contrast, the second substrate's top face imprints the two arms' footprints. The reflection phases are altered by adjusting the overlapped arms' lengths between the two dielectric substrates. This allows one to redirect and reconfigure the scattering fields' patterns in the desired coverage area. Based on the novel configuration of unit cells, the cross-polarization of the reflected waves can be significantly reduced with the interleaved and mirrored cell constellation. A 21 × 21-element MRRS in the format of reflectarray is designed at 28 GHz to validate the effectiveness through experimental measurements. The measured results show 4% 1 dB and 7% 3 dB gain bandwidths. The maximum gain at 28 GHz is 25.6 dB, and the aperture efficiency is approximately 37.8%.