Single-Layer, Dual-Passband, High-Reject, Beam-Pointing FSS for SatCom Applications

The paper presents a single-layer, dual-passband, high-reject frequency selective surface (FSS) transmit array radome for satellite communication (SatCom) applications. The proposed FSS comprises a novel hybrid loop-modified split-ring resonator (HLM-SRR) unit cell structure. Their design is optimized using numerical techniques and a semi-analytical procedure based on equivalent circuit theory. Unlike the previously proposed FSS limited to dual-band functionality, this FSS suppresses both out-of-band and inter-band signals (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\boldsymbol{&gt;} \mathbf{2 5}$</tex> dB) while maintaining skirt-selective roll-off exceeding <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{2 5 ~ d B / 0. 2 5}$</tex> GHz at all frequency response edges. The finite FSS array radiated effectively with a narrow half-power beamwidth (< 8°) and minimized side lobe levels (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$&gt;13 ~\text{dB}$</tex>). Additionally, the unit cell exhibited a beam-pointing dependency on the incidence angle with retained filtering response, which is vital for SatCom constellations. Full-wave simulations of filtering and radiation properties are presented.