2D Leaky-Wave Antenna with All-Dielectric Partially Reflecting Surface at mm-Wave Frequencies

High surface roughness and skin depth losses are present in metallic structures which are part of antennas at mm-wave and sub-THz frequencies. Replacing metal with low-loss dielectrics could help mitigate overall losses. In this paper a high directivity 2D leaky-wave antenna (2D-LWA) is designed with an all-dielectric partially reflecting surface (PRS), at 64.3 GHz. Low-loss commercially available substrates are used and assembled to form the antenna stack. The antenna is fabricated and measured, showing a good agreement with simulation. A maximum broadside gain of 17.7 dBi is obtained at 64.5 GHz.