3-bit Programmable Reflective Metasurface

A 3-bit programmable reflective metasurface is proposed in this paper. Each unit cell of the metasurface includes 4 pin diodes and by changing the states of the pin diodes, metasurface produces 8 distinct phase responses of 0,π/4, π/2,3π/4, π, 5π/4,3π/2 and 7π/4 to mimic eight states: 000, 001, 010, 011, 100, 101, 110 and 111. The 3-bit programmable metasurface has a better flexibility than 1-bit and 2-bit programmable metasurface to control EM waves.