Comparison of Additively Manufactured and Machined Antenna Array Performance at Ka-Band

Abstract

Additive manufacturing (AM) is a rapidly developing field, which potentially decreases the manufacturing costs and enables increasingly complex antenna shapes. Metal-based AM might be particularly useful for manufacturing antennas at millimeter-wave (mm-wave) range, because these antennas are physically small enough making AM cost efficient, and manufacturing accuracy could still suffice for good electrical performance. In this letter, two additively manufactured and identical machined fully metallic $Ka$-band Vivaldi antenna arrays are compared. The manufactured antenna arrays are compared using RF measurements to conclude the feasibility of AM for manufacturing antenna arrays at mm-wave frequencies. Comparison of the measured radiation patterns and realized gains of each of the antenna arrays between 26 and 40 GHz shows close to identical radiation patterns for all the arrays. A loss in realized gain of 0.5-1.5 dB is observed in the AM arrays when compared to the machined array due to the used materials and the surface roughness.