W-Band Ultrathin Hybrid Huygens Metasurface Transmit-Reflectarray With Independent Regulation of Transmit-Reflected Wave

A novel high-efficiency ultrathin hybrid Huygens metasurface (HMS) with independent regulation of transmit-reflected wave is proposed. Dual pairs of U-shaped and cross-shaped patches are used to form the multiresonance hybrid HMS elements and realize efficient transmission and reflection simultaneously. Owing to the polarization orthogonality, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Y</i>-polarization transmission and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">X</i>-polarization reflection waves can be regulated independently. Therefore, dual-functional array of efficient transmission and reflection can be achieved based on the hybrid HMS. Subsequently, a hybrid HMS-based transmit-reflectarray (TRA) prototype is designed, fabricated and measured. The measured peak aperture efficiencies are 46.33%/40.09% at 85 GHz with big bandwidth over 16%/28% for RA/TA. Different from conventional multilayer arrays, the proposed TRA is implemented solely on single-layer substrate; thus, the dielectric loss is minimized and the design is greatly simplified. Benefiting from the advantages of high efficiency, single layer, as well as independent regulation capability of transmit-reflected waves, the proposed hybrid HMS-based TRA is expected to be a competitive candidate for communication systems in high-frequency band of millimeter wave (MMW).