Unit-Cell Loaded With PIN Diodes for 1-Bit Linearly Polarized Reconfigurable Transmitarrays

In this letter, a reconfigurable unit-cell for transmitarray antenna working at X-band is presented. It is designed to provide 1-bit phase quantization using p-i-n diodes. The unit-cell is based on multilayer frequency selective surfaces with the use of two substrates and a combination of a C-patch and a ring slot loaded by a rectangular gap. It is optimized using full-wave electromagnetic simulation and verified by using waveguide simulator. The experimental results show that the unit-cell provides two values of the transmission phase with a step of 180 degrees at 11.5 GHz. Furthermore, the unit-cell has a low thickness of 0.19 lambda(0), and is low-cost and easy to fabricate.