Dual-polarized low loss reflectarray cells with MEMS-based dynamic phase control

X-band reconfigurable reflectarray (RRA) cells having two, three, and four discrete reflection phase states are presented in this paper. The cell topology enables independent dynamic reflection phase control of each linear component of a dual-polarized wave. The reflection phase step deviation is smaller than the quantization error in 12.5% bandwidth for the two and three states designs and in 6.5% bandwidth for the four states design. Owing to particular design considerations and implementation in monolithic micro-electromechanical systems (MEMS) fabrication process, the average reflection loss is kept very low, from 0.3 dB for the two states design to 0.8 dB for the four states design. Measurement results of the two states (1-bit) prototype are in good agreement with the simulation results, thereby confirming the viability of the concept.