Engineered Quasi-Periodic Metasurface Antenna Based on Huygens' Meta-Scatterers for Wideband Millimeter-Wave Beamforming

This paper proposes an engineered quasi-periodic metasurface (QPM) antenna based on highly-transmissive Huygens' meta-scatterers (HMS) for efficient wideband millimeter-wave beamforming. A via-less, single-layer HMS with subwavelength periodicity is designed using axially symmetric rectangular split-ring structures to simultaneously support electric and magnetic dipole responses. The Huygens' resonance behavior, achieved by co-locating electric and magnetic resonances at closely spaced frequencies, enhances the bandwidth and ensures robust transmission performance with near-unity amplitude and full 360° phase coverage. Subsequently, a QPM is synthesized using four different variants of HMS arranged in a 25 × 25 quasi-periodic array according to the 2-bit quantized phase distribution. Further, the designed QPM is spatially excited through a dielectric horn antenna (DHA) positioned at an optimum focal distance. The complete antenna is fabricated and its performance is validated in an anechoic chamber. Experimental results demonstrate a 3-dB gain bandwidth of 18.4% from 25.7 GHz to 30.9 GHz with a peak measured gain of 27.6 dBi and gain enhancement of 13.7 dB at 28 GHz. The proposed QPM antenna achieves an aperture efficiency of 68.6%, making it a compact, efficient, and fabrication-friendly solution for mm-wave beamforming in advanced wireless systems.