Wideband Transmitarray Unit-Cell Design With 1-Bit Phase Control and Twistable Polarization

In this letter, we propose a wideband unit-cell for electronically reconfigurable transmitarray antennas working at the X -band. The unit-cell is based on a multilayer structure that has the capability to rotate the polarization of the transmitted wave to be orthogonal to the polarization of the incident wave. Two p-i-n diodes are integrated into the unit-cell to control the phase shift with 1-bit phase resolution. Both simulated and measured results agree that the unit-cell provides two phase states with a step of 180°, covering a wide −3 dB transmission bandwidth of 26%. Furthermore, the unit-cell exhibits a simple design and a low thickness of 0.16\lambda _{\mathrm {0,}} allowing a low-cost and easy fabrication.