Design of the 1-Bit Unit Cell for A Dual-Polarized Broadband Reflectarray

A broadband dual-polarized 1-bit unit cell for beam scanning reflectarray is proposed. The unit cell includes elements in two orthogonal polarization directions. Each element is composed of a pair of tightly coupled dipoles and a pair of phase delay lines. RF switches are loaded on the delay lines to alter the unit cell's reflection phase. Simulations demonstrate that the unit cell can achieve 1-bit phase shift from 4 to 6 GHz. To verify the beam scanning capability, the radiation pattern of a reflectarray that includes 11×13 unit cells is calculated. The results indicate that this design can achieve ±30° beam scanning from 4 to 6 GHz.