Figure 6.

Generation of arbitrary multibit programmable phases. Reproduced from [114]. (a) Conceptual illustration of arbitrary multibit programmable metasurfaces under the control of an FPGA. (b) Vector synthesis in the complex plane for generating the multibit programmable phases. Equivalent phase coverage: (c) at the central frequency and (d) at the +1^st harmonic frequency. (e) Comparison of 3D scattering patterns with respect to the original 1-bit and 2-bit phases and equivalent 3-bit and 4-bit phases for beam steering.