Terahertz Dielectric Phased-Array Antennas Based on Effective-Medium Platform for Wireless Communications

The terahertz frequency band offers unprecedented bandwidths for next-generation wireless communications, but suffers from significant free-space path loss that necessitates highly directive antennas. Beam-steering antennas are therefore essential to dynamically align high-gain beams and maintain link reliability in practical terahertz wireless systems. In this work, we propose a phased-array antenna based on an all-silicon effective-medium waveguide platform. The proposed architecture integrates a feeding network, terahertz phase shifters, and a dense waveguide array terminated by dielectric rod antennas, with each component realized in a modular hollow waveguide package. Compared with conventional terahertz phased arrays that achieve phase control in either the electronic or photonic domain, the proposed design enables direct phase tuning in the terahertz domain using widely accessible phase shifters, while maintaining low loss, broad bandwidth, and scalability. As a proof of concept, a two-element phased array is demonstrated, achieving continuous beam steering over± 20∘at the 300-GHz band. The impact of interwaveguide coupling and radiator mutual interaction is systematically investigated. Wireless communications experiments further validate the beam-steering functionality, supporting transmission data rates up to 40 Gbit/s with 16-QAM modulation and real-time high-definition video transmission. The proposed design demonstrates the feasibility of all-dielectric waveguide platforms for dynamic beam-steerable antennas and lays the foundation for efficient fully integrated terahertz phased arrays for 6G and beyond.