Multiple beams direction and power control using passive lossless metasurface by surface waves

In this work, a passive lossless metasurface can arbitrarily control multiple beams' direction and power utilizing surface waves is proposed. The incident wave is coupled into surface wave on the metasurface, then the surface wave propagates along the metasurface, and continuously decouples into multiple radiation beams in the one side of the metasurface. Moreover, these multiple radiation beams’ direction and power can be arbitrary controlled by the design of surface impedance of metasurface. In our work, a method for accurate estimation of coupled (decoupled) surface wave amplitude is established, so the surface impedance determined by the surface wave and the radiation beams can be precisely designed and passively lossless. The metasurface having two equal power radiation beams with −30⁰ and 60⁰ radiation angles, and the metasurface having two unequal power radiation beams also with −30⁰ and 60⁰ radiation angles are designed as examples, respectively, verifying our design method.