“…Frequency selective surfaces (FSSs) are periodic structures consisting of planar metallic arrays on a dielectric substrate, designed to selectively transmit, reflect, and absorb electromagnetic waves at specific frequencies 1 . They find widespread applications in mitigating electromagnetic interference (EMI) across various communication bands, including GSM, 2 LTE‐2.1 GHz, 3 WLAN/WiMax, 4,5 and sub‐6 GHz in 5G new radio (NR), 6 often spanning multiple bands 7 . The ever advance of 5G NR communication has impelled the investigations into the millimeter wave (mmW) bands, such as n257 (26.5–29.5 GHz), n258 (24.25–27.5 GHz), and n260 (37–40 GHz) 8 .…”