A Unit Cell of Reconfigurable Reflectarray with 1-Bit Phase-shifting and Amplitude-controlling Characteristics

Reconfigurable reflectarray has attracted a great deal of interests in past few decades. However, the current research mostly focus on achieving the phase-shifting of unit cell. In this paper, a reconfigurable reflectarray unit cell with 1-bit phase-shifting and amplitude-controlling characteristics is proposed. The unit cell has a multilayer structure that consists of two frequency selective surface(FSS) layers, and a reflection layer. The top and the middle layers act as FSSs that are responsible for the amplitude-controlling; the rectangle patches with ground are placed on the reflection layer that is utilized to achieve phase-shifting and reflect the EM waves. Full-wave simulations are carried out to verify the performance of the proposed design. The simulated results show that $180^{\circ}$ phase-shifting and 10 dB amplitude-controlling are both achieved. In addition, the surface current distribution is also presented to analyze the working principle of the unit cell. The proposed reflectarray element can be potentially applied in low-sidelobe beam-scanning reflectarray design.