An Interlaced Dual-Phased Aperture Antenna for Multidirectional Wide-Angle Coverage at SubTHz

This letter describes a compact multi-directional beam-switching antenna that achieves wide angular coverage in the sub-terahertz band by combining the main beam with grating lobes. The proposed design combines co-phased and alternating-phased radiating slot waveguide arrays with different slot offsets to generate complementary beams and eliminate null regions, thereby maximizing coverage. The two arrays are interlaced and share a common aperture, while groove patterns are incorporated to maintain gain uniformity and reduce mutual coupling caused by interference between arrays with different phases. The fabricated antenna comprises a 3 × 20 co-phased array and a 4 × 20 alternating-phased array, operating across 247.4–254.3 GHz with a peak realized gain of 22.3 dBi and less than 2.1 dB variation across beams. At a center frequency of 253 GHz, the antenna forms beams in seven directions, covering an angular range of 88°.