Metallic 3-D Printed Antennas for Millimeter- and Submillimeter Wave Applications

This paper presents a study to use the metallic three dimensional (3-D) printing technology for antenna implementations up to 325 GHz. Two different printing technologies and materials are used, namely binder jetting/sintering on 316L stainless steel and selective laser melting (SLM) on Cu–15Sn. Phases, microstructure, and surface roughness are investigated on different materials. Balancing between the cost and performance, the manually polished Cu–15Sn is selected to develop a series of conical horn antennas at the E-(60–90 GHz), D- (110–170 GHz), and H-band (220–325 GHz). Good agreement is observed between the simulated and measured antenna performance. The antennas’ impedance bandwidth ( $\vert S_{11}\vert ) cover the whole operational band, with in-band gain of >22.5, >22, and >21.5 dBi for the E-, D-, and H-band antennas, respectively. Compared with the traditional injection molding and micromachining for metallic horn antenna implementation, the 3-D printed metallic horn antenna features environmental friendliness, low cost, and short turn-around time. Compared with the nonmetallic 3-D printed antennas, they feature process simplicity and mechanical robustness. It proves great potential of the metallic 3-D printing technology for both industrial mass production and prototyping.