Abstract：In this paper, we propose a “[]” shaped unit. The reflection phase of an electromagnetic wave can be changed when changing the size of a cell. Ten units of different sizes are selected after optimization in order to form a metasurface. Under the condition of vertical incidence of the TE wave, the phenomene of abnormal reflection of -30°deflection of the reflected wave is observed at the frequency point, and for the reflected waves at several other frequencys in X-band, there appears obvious abnormal reflection phenomenon, which indicates that the metasurface designed has broadband characteristics. In this paper, we give a metasurface with phase gradient on X and Y axes. From the simulation results, it can be seen that the reflected wave is deflected by 30 degrees along the -X and -Y axis directions. Finally, the back RCS of the metasurface is observed, and the RCS of the designed metasurface is 5~10dB lower than that of the metal plate with the same size, which shows that the metasurface has a characteristic of low scattering.
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2017, Vol. 18 
