Highly Integrated Full-Space Coding Metasurface for LP and CP Waves Manipulation Spanning Millimeter-Wave and Sub-THz Bands

Coding metasurfaces (MSs) provide an effective strategy for designing highly integrated devices due to their powerful ability to flexibly manipulate the wavefront of electromagnetic (EM) waves. To date, it remains a great challenge to theoretically construct and experimentally verify highly integrated MSs for manipulating both linear polarization (LP) and circular polarization (CP) waves in full-space at millimeter-wave (mmWave) and sub-terahertz (sub-THz) bands. In this work, a highly-integrated, low-crosstalk, six-channel coding meta-atom is developed using hybrid phase manipulations, which can achieve independent full-space phase controls for three LP channels and three CP channels across three mmWave and sub-THz bands. To validate the concept, we designed and fabricated a compact coding MS, including refracted four-beam splitting for LP wave at 65 GHz; radar cross section (RCS) reduction, anomalous reflection and dual-vortex beam generation for LP and CP waves at 0.12 THz; two-beam splitting for two decoupled CP waves at 0.154 THz. All the theoretical, simulated, and experimental results agree well with each other. The developed highly integrated MS with multiple independent channels presents a promising candidate for future advanced 5G and 6G systems.