Design and Measurement of a 220 GHz Wideband 3-D Printed Dielectric Reflectarray

A wideband high-gain terahertz dielectric reflectarray working at 220 GHz is investigated both theoretically and experimentally. The reflectarray unit cell consists of a ground plane and a dielectric block. The reflection phase is obtained by adjusting the height of the block. Using the reflection phase computational algorithm, a dielectric reflectarray composed of 40 × 40 unit cells is designed and fabricated through three-dimensional (3-D) printed technology. Four types of 3-D printed material are measured using the THz time-domain spectroscopy system. It is found that the maximum gain and gain bandwidth of the proposed reflectarray is 31.3 dBi and 20.9%, respectively. Measured results are in reasonable agreement with simulated results. This result is an important step toward the 3-D printed THz dielectric reflectarray above 220 GHz.