An Ultrathin, Dual-Band, and Dual-Polarized Metalens Antenna Based on Double-Resonant Huygens' Metasurface

In this letter, we demonstrate a double-resonant Huygens' metasurface. The double Huygens' resonances serve as the bridges connecting several nonresonant passbands, achieving good transmission performance over an ultrawideband range and available transmission phase coverage far beyond 360 degrees. Then, a dual-band dual-polarized 3-bit phase scheme is proposed to independently obtain sufficient phase coverages at 28/38 GHz. When used for planar lens antenna design, good dual-band radiation performance is achieved. In the 28 GHz band, the measured peak gain is 29.14 dBi at 28.5 GHz with an aperture efficiency of 44.87% and a 3 dB gain bandwidth of 18.2%. In the 38 GHz band, the measured peak gain is 32.03 dBi at 38 GHz with an aperture efficiency of 47.25% and a 3 dB gain bandwidth of 8.7%.