Optically Transparent Tri-Wideband Mosaic Frequency Selective Surface with Low Cross-Polarisation

Abstract

Acquiring an optically transparent feature on the wideband frequency selective surface (FSS), particularly for smart city applications (building window and transportation services) and vehicle windows, is a challenging task. Hence, this study assessed the performance of optically transparent mosaic frequency selective surfaces (MFSS) with a conductive metallic element unit cell that integrated Koch fractal and double hexagonal loop fabricated on a polycarbonate substrate. The opaque and transparent features of the MFSS were studied. While the study on opaque MFSS revealed the advantage of having wideband responses, the study on transparent MFSS was performed to determine the optical transparency application with wideband feature. To comprehend the MFSS design, the evolutionary influence of the unit cell on the performance of MFSS was investigated and discussed thoroughly in this paper. Both the opaque and transparent MFSS yielded wideband bandstop and bandpass responses with low cross-polarisation (−37 dB), whereas the angular stability was limited to only 25°. The transparent MFSS displayed high-level transparency exceeding 70%. Both the simulated and measured performance comparison exhibited good correlation for both opaque and transparent MFSS. The proposed transparent MFSS with wideband frequency response and low cross-polarisation features signified a promising filtering potential in multiple applications.

Dual‐band sub‐6‐GHz frequency filtering with optically transparent single‐layer dual‐polarized smart surface

“…One of the features is seamless integration on aforesaid objects, which may comprise everyday materials, that can be used on walls, windows, and floors by providing low-cost and low-profile characteristics. On the other hand, such surfaces should provide high isolation, support multiple polarization, 2,[6][7][8][9]11 and keep stability for a wide range of oblique incidence angles. Operating at dual-band or wide-band frequencies is another requirement of smart surfaces.…”