부산대학교 도서관

A low-profile single / twin- beamforming digital metasurface lens (DMSL) antenna is proposed for millimeter-wave applications. The complete antenna prototype comprises of 1-bit coded transmission-type DMSL and a slot-coupled microstrip patch antenna (MPA) as feed source placed at a focal distance of 20 mm beneath the DMSL. The proposed DMSL comprises of slotted meta-atoms arranged in an array. The adopted meta-atom is highly insensitive to wave polarization and oblique angle of incidence of upto 60°. To achieve focused beam in the broadside direction antenna configuration with DMSL-1 is adopted which is constructed using an array of 25 × 25 meta-atoms. The maximum gain of 19.5 dBi is achieved for DMSL-1 antenna configuration in the broadside direction showing a gain enhancement of 13.4 dB. Further, the antenna with DMSL-2 is designed to split and focus the beams simultaneously in ±30° direction resulting in two equal beams each having a gain of 16.6 dBi and a gain enhancement of 10.5 dB. The f/D ratio for both antenna configurations is 0.2 resulting in a compact antenna.