Fig. 1. The radiation pattern of induced electromagnetic multipoles (up to quadrupoles) under planewave excitation^[34]. The incident planewave prorogates from the left with in-plane electric field. The blue and purple curves indicate the out-of-plane and in-plane scattering pattern, respectively. The electric field polarizations in the forward and backward scattering directions are shown by red arrows

Fig. 2. The microscopic interpretation of the Brewster effect. (a)(b) p- and s-polarized wave impinges onto a pure dielectric medium; (c) s-polarized wave impinges onto a medium with both electric and magnetic response. The red cross-circles and double-sided arrows represent equivalent EDs, and the blue symbols represent equivalent MDs. The red curves show the radiation pattern of each ED, and the purple curves show the radiation pattern of interfering EDs and MDs

Fig. 3. The multipole interference model of GKE when an artificial periodic structure is suspended beyond the interface. (a)-(c) The s-polarized wave incidence; (d)-(f) The p-polarized wave incidence. The medium 1 is air and the medium 2 is a pure dielectric. The red double-sided arrows and cross-circles represent equivalent EDs, and the blue ones represent MDs. The insets represent the far-field radiation pattern of a unit cell above the interface

Fig. 4. Co-modulation of both s- and p-polarized waves by the double-layer S-ring FSS^[31]. (a) The 3D schematic diagram of the FSS; (b) the current density distribution of rings A and B under the incidence of both s- and p-polarized planewaves with the incident angle 20° and the incident plane xOz plane; (c) the modulation of GBE by the suspension height; (d) the far-field radiation pattern of a unit cell corresponding to the zero-reflectance points of Fig. 4 (c)

Fig. 5. The design of ultra-wide angle high transmission FSS and simulated results. (a) The 3D schematic diagram of the FSS; (b) the variation of s- and p-polarized transmittance versus frequency and incident angle, where the realization of UWAHT is marked by the black dashed lines; (c) the radiation patterns of a unit cell when s- ang p-polarized waves impinge at 20° and 60° incidence, the light brown, light green and grey curves represent the radiation of the S ring structure, the dielectric slab and their superposition, respectively; (d)(e) the current distribution and the bar graph of multipole expansion coefficients of the vertical and horizontal S ring when s- and p-polarized waves impinge at 60° incidence

Fig. 6. The near isotropic wide-angle high-transmission FSS. (a) The schematic diagram of the FSS. (b)-(e) the variation of transmittance versus frequency and incident angle when s- and p-polarized waves impinge at φ=0° and φ=45°

Fig. 7. The schematic diagrams of the equivalent model of an ideal phased array. (a) The equivalent ED array; (b) E-plane scanning; (c) H-plane scanning; (d) the variation of the E-plane and H-plane reflection coefficients versus radiated angle, the region of ρ<1/3 is marked by the grey shadow

Fig. 8. The dual-polarized slot antenna array loaded by an S-ring array. (a) The schematic diagram of the antenna array; (b)(c) the simulated results of E- and H-plane reflection coefficients after and before loading the S-ring array