Transparent dual-band wide-angle polarization-insensitive single-layer frequency selective surface for mm-wave 5G communication systems

Abstract

A highly transparent single-layer frequency selective surface (FSS) with an optical transmittance of 92.7% at 550 nm, designed for 5G communication systems operating in dual frequency bands of 26 and 38 GHz is proposed. The dual-band FSS not only achieves high optical transparency but also maintains good electrical performance. The transmission performance of the FSS is stable to the polarization and angles of incidence for electromagnetic waves. As a proof of concept, the FSS with periodic square loops patterned on a 188-µm-thick substrate is fabricated. Each loop is constructed with metallic mesh electrodes having a pitch of 10 µm. Measurements are conducted using two different systems: a free-space measurement system and a vector network analyser-based material characterization kit. After calibrating the measurement systems, the scattering parameters of the fabricated surface are measured. The results obtained from both measurement systems show good agreement and also agree with the simulated results. The designed surface has an insertion loss of less than 3 dB in the dual passband region. The proposed dual-band FSS has the merits of polarization independence, angular insensitivity, and high transparency.