Reconfigurable metasurfaces integrated with tunable active devices have become a prominent research hotspot in electromagnetic engineering, enabling dynamic and flexible manipulation of electromagnetic waves. However, many of the reported reconfigurable metasurfaces can only achieve single function, and a few multifunctional designs also face bottlenecks such as narrow operating bandwidth, poor angular stability, and complex bias control networks, which limit the practical applications in smart electromagnetic systems. To solve these problems, this paper proposes one compact and highly integrated reconfigurable metasurface, realizing integration and reversible switch of dynamically tunable microwave absorption and high-efficiency linear polarization conversion.
In the design, four SMP1302-079LF PIN diodes are embedded into the centrosymmetric metasurface unit, and a coaxial feeding structure with 52 nH choke inductor is adopted to independently control the working state of the diodes. The electromagnetic characteristics and working mechanism of the designed metasurface are systematically analyzed by full-wave simulation and theoretical calculation. When the same bias voltage is applied to all PIN diodes, the metasurface maintains a centrosymmetric structure and operates in the tunable absorption mode. The simulation results show that the absorptivity is larger than 90% in 4.08–9.12 GHz, with the relative bandwidth of 68.1%, and the absorption intensity can be tuned over 10 dB with a peak tuning range of 25 dB. When different bias voltages are applied to adjacent PIN diodes, the impedance symmetry of the metasurface is broken, and the metasurface switches to the linear polarization conversion mode. In this mode, the polarization conversion ratio (PCR) exceeds 90% in 4.11–9.03 GHz, and the peak PCR reaches 99%. The physical mechanism reveals that the polarization conversion relies on the electrically controlled asymmetric electromagnetic response, which is more flexible than the traditional geometric asymmetry design. In addition, the metasurface maintains stable performance with incident angles up to 60° for both TE and TM polarizations in two working modes, showing excellent angular and polarization stability.
A prototype with 9×9 units (180×180 mm²) is fabricated and measured by the arch method following GJB2038A-2011 standard. The measured results agree well with the simulation data, verifying effectiveness of the design. The proposed metasurface has the advantages of compact structure, flexible function switch, wide bandwidth and strong angular stability, showing extensive application prospect in intelligent stealth, adaptive camouflage and anti-interference wireless communication systems.