Compact Folded Fresnel Zone Plate Lens Antenna for mm-Wave Communications

A low-profile single-polarized folded Fresnel zone plate (FZP) lens antenna is presented for 5G millimeter-wave point-to-point communications in V-band. This antenna has two benefits: 1) the compactness of folded reflector structures made of a trans-reflector and a twist-reflector, and 2) the simplicity of FZP lenses. The idea of the folded structure is to triple the electrical path compared to nonfolded configurations. The combination of all these benefits leads to a very low-profile, high-directive, broadband, and low-cost antenna, as confirmed by measurements. A measured peak gain of 32.7 dBi is obtained at 60 GHz, with almost flat gain curve from 57 to 64 GHz, with a half-power beamwidth of 3°, compliant with ETSI V-band class 2 standard.