All-Dielectric 2-Bit Transmitarray Antenna for Sub-Terahertz Applications

Abstract

This paper presents an all-dielectric 2-bit transmitarray antenna designed for sub-terahertz operation at 303 GHz. The antenna uses a digitally quantized phase distribution, which simplifies the design and enables precise beam control while reducing fabrication complexity. Each unit cell comprises a silicon post embedded in a quartz substrate with a central hole. The balanced electric and magnetic resonances in the unit cell provide high transmission and 360° phase coverage. The 28 × 28 transmitarray, illuminated by a horn antenna, achieves a broadside beam with a realized gain of 27 dBi and an aperture efficiency of 25%. The results demonstrate that a simplified 2-bit all-dielectric architecture can achieve effective beam focusing at sub-terahertz frequencies, providing a practical trade-off between performance, design complexity, and fabrication feasibility.