A Single-layer Reflectarray Antenna for Sub-THz Applications

In this work, a single-layer reflectarray element with high efficiency is presented. The element of the reflectarray is composed of metal patches printed on both sides of the substrate. A phase coverage of 360° can be achieved by adjusting the upper patch arm length, the expansion coefficient, and the contraction coefficient. Besides, the reflection amplitude is good. Based on these settings, a 17×17 reflective array antenna is designed. The maximum gain of this antenna is 23.75 dBi. In addition, the antenna achieves a 1-dB gain bandwidth of 15% and a 3-dB gain bandwidth of 33%.