Integrated Photonics‐Assisted THz Beamformer for Fast Beam Squint‐Free Steering and Wireless Communication

ABSTRACT Photonic‐assisted terahertz (THz) wireless communication is a promising solution for future high‐capacity wireless networks. However, the low output power and severe propagation loss of THz waves limit transmission distance. To overcome these challenges and support dynamic multi‐user connectivity, we demonstrate an integrated photonics‐assisted THz beamformer enabling broadband, beam‐squint‐free beam steering in the D‐band, based on silicon four‐channel tunable optical true‐time delay lines (OTTDLs). Each OTTDL combines an 8‐bit switchable delay and a continuously tunable delay unit, achieving a total continuous delay range of 0–394.24 ps. By providing true time delays, the proposed beamformer maintains a consistent beam direction across a wide operating bandwidth, thereby fundamentally eliminating beam squint. Leveraging this chip and a 1 × 4 dielectric rod antenna array, we achieve beam steering with a total beam switching time of 120 ns and a maximum angle of ±20.19°. We demonstrate wireless transmission with a line rate of 100 Gb/s at two distinct angles. To the best of our knowledge, this is the first integrated THz beamforming system that realizes broadband, beam‐squint‐free operation using OTTDLs. This work represents a significant step toward scalable, low‐latency, and high‐speed THz wireless networks, offering a viable pathway for dynamic beam management in future 6G systems.