©2021 The MITRE Corporation. ALL RIGHTS RESERVED 
Approved for public release. Distribution Unlimited 21-0672Wideband phased array antenna technology is leveraged in a variety of use cases including radar, communications, and electronic warfare. In 2015, MITRE introduced a new class of phased array antenna technology called the Frequency-Scaled, Ultra-Wideband, Spectrum Element (FUSE) array. Since then, MITRE continues to conduct research to advance the technology improving electrical performance as well as manufacturing design performance addressing size, weight, power, and cost (SWaP-C), environmental requirements, and manufacturing challenges. Initially, this array was exclusively manufactured using a combination of five conventional and advanced manufacturing methods: computer numerical control (CNC) machining, overmolded polymers, wire electrical discharge machining (EDM), metal plating, and 3D printing. While this manufacturing design produced parts effectively and demonstrated great empirical / measured agreement with radio frequency (RF) simulations, it introduced cost, manufacturing complexity, and lead time challenges.To address these challenges, additive manufacturing (AM) of the FUSE antenna was explored starting in 2017. In this paper, FUSE antennas manufactured using two AM fabrication methods are described along with a comparison of the as-manufactured and final part quality. While the redesigned AM FUSE experienced a slight performance reduction compared to the original FUSE design, manufacturing complexity was reduced to one or two steps (depending on the array design), fabrication and labor-intensive assembly costs were reduce by up to 50%, and lead time to fabricate the FUSE antenna was reduced from months to a few weeks. Furthermore, due to the unique capabilities of AM, internal latticed structures can produce FUSE antennas with 50% weight reduction in some instances. Switching to AM sparked creativity to explore new shapes and designs that were previously impossible to build. It should be noted that most recent FUSE designs are simulated to perform identically to the original design, recovering aforementioned performance reductions, and are currently in the design and manufacturing stage at The MITRE Corporation.A follow-on study was conducted to compare the manufacture of two FUSE antennas operating between 1 and 6 Gigahertz (GHz) with identical geometries but built from two additive manufacturing processes: direct metal laser sintering (DMLS) and stereolithography (SLA). Note that the SLA was also metal plated with a nickel-copper combination for structure and electrical conductivity. This design is referred to as the, “plated-stereolithography (p-SLA) FUSE”. Though the different manufacturing processes necessitated some real-world geometric, material, and component differences, the study found that electrical performance for both arrays was nearly identical. Differences in the two arrays were related to slight deviations in overall dimensions and tolerancing due to different 3D printer specifications, surfaces roughness differences between materials and printing processes, and unique mechanical behaviors exhibited by part features produced from each additive process (e.g. features deflecting due to internal stress concentrations). Ultimately, the array exhibited all features and performance of general additively manufactured FUSE designs found in recent literature: reconfigurable subarrays, low cross-polarization and active VSWR, geometric scalability per operating frequency range, and a relatively wide-bandwidth ratio. This study has informed the ability to realize such unique RF structures utilizing established additive manufacturing technologies while achieving identical electrical results allowing the end-user to balance such attributes as SWaP-C, material properties, and environmental requirements in final design selection.&nbsp;©2021 The MITRE Corporation. ALL RIGHTS RESERVED 
Approved for public release. Distribution Unlimited 21-0672

Additive Manufacturing Design of the Frequency-Scaled, Ultra-Wideband, Spectrum Element (Fuse) Phased Array Antenna

Paper Proceedings: https://asmedigitalcollection.asme.org/IMECE/IMECE2021/volume/85543

ASME 2021 International Mechanical Engineering Congress and Exposition (IMECE2021)

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.