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 (|S
₁₁
| <; -20 dB) 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.