Polarization-Controllable Dual-Band Antennas Using Nonbianisotropic Complementary Split Ring Resonator-Loaded Metasurfaces

In this work, compact polarization-controllable dual-band antennas are designed, prototyped, and experimentally verified, which are composed of a planar monopole on top of a dual-layer truncated metasurface (MS) containing patches and nonbianisotropic complementary split ring resonators. By tailoring the dispersive properties of the MS, the relative phase difference of resonances associated with surface waves supported along two orthogonal horizontal directions can be independently engineered at two separate frequency bands, thereby giving rise to compact dual-band antennas with controllable polarization in each band. Three proof-of-concept example antennas with a form factor on the order of
$0.3\lambda _{\mathbf {0}}\times 0.3 \lambda _{\mathbf {0}} \times 0.04 \lambda _{\mathbf {0}}$
were designed and measured. The first one provides circularly polarized (CP) radiation with the same sense of polarization in both bands, the second one offers linearly polarized (LP) radiation in the lower band and CP radiation in the higher band, while the last one achieves CP radiation in the lower band and LP radiation in the higher band. The measured results agree well with the simulation predictions, thus verifying the proposed concept and specific antenna designs.