Improved compact, wideband, low-dispersion, metamaterial-based MEMS phase shifters

This paper reports compact, wideband, low-dispersion, metamaterial-based phase shifters with lower loss, wider bandwidth, and fewer MEMS switches than previous designs. The present design is based on a novel 90° unit cell which uses two synchronized MEMS switches that are actuated and unactuated in unison for the through and delayed states, respectively. By combining three of these 90° unit cells with a 45° unit cell of previous design, a 3-bit phase shifter is designed to have smaller than 8 mm² footprint, less than 20° root-mean-square phase error, less than 2.0 dB insertion loss, and higher than 17 dB return loss between 22 GHz and 27 GHz.