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 to manufacture antennas at mmwave range, because there antennas are physically small enough making additive manufacturing cost efficient, and manufacturing accuracy could still suffice for good electrical performance. In this paper, two additively manufactured and an identical machined fully metallic Ka-band Vivaldi antenna arrays are compared. The manufactured antenna arrays are compared using RFmeasurements 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.

Metal 3D-Printing of Waveguide Components and Antennas: Guidelines and New Perspectives

“…The recommended rounding radius is at least 0.3 mm (although the larger, the better). The reason for this recommendation is the avoidance of local overheating when printing a certain edge, which can result in deformations of the structure [24].…”

A Modular Dual-Polarized Ka-Band Vivaldi Antenna Array

“…An antenna array prototype is designed integrating previously presented ideas [27]- [29]. The core idea of the antenna array is to be wideband, beam-steerable, modular, and to theoretically enable the array to be extended to any size and shape.…”

“…The antenna element is a single piece of metal and can be manufactured using additive manufacturing or electric discharge machining. It is based on the design presented in [27]- [29] with the dimensions scaled and optimized for the frequency range up to 30 GHz. One antenna element is dual polarized, and the elements can be used to construct arrays of various sizes.…”

“…316L stainless steel was selected as the material to manufacture the antennas based on experience in [29]. Additionally, a trial run with the same manufacturing method was made using copper powder.…”

“…In this paper, the objective is to extend the design presented in [27]- [29] and realize the envisioned integration capability of these structures. In the previous works, a similar type of antenna element design is used to confirm the feasibility of the surface-mounted antenna design and the applicability of additive manufacturing to the design to retain good performance up to 40 GHz.…”