An Agile Additively Manufactured 5G/mm-Wave RF Front-End with Multi-Layer Conformality and Printed RF VIAs for Ultra-Wideband and Miniaturized Systems

This paper presents the first fully additively manufactured (AM) multi-layered RF front-end (RF-FE) for mm-wave frequencies (20-30 GHz), integrating active devices, passive printed structures, and RF signals routed on both outer layers. The system features flexible inkjet- and screen-printed RF VIAs with insertion loss between 0.58 dB and 1.64 dB and minimal bending-induced degradation. Its multi-layer architecture enables significant miniaturization, ideal for compact, low-cost, and sustainable mm-wave modules in wearable devices, autonomous UAVs, and smart cities. The design achieves inkjet-printed feature sizes down to 60 um, critical for mm-wave filters, and incorporates a monopole antenna array with up to 9 dBi gain, demonstrating robust planar and conformal performance. Leveraging AM, this work establishes a pathway for miniaturized, flexible, and cost-effective RF systems, addressing key challenges in advanced communication and sensing applications.