Additively manufactured microstrip patch antennas in flat, curved, and embedded configurations

Abstract

Microstrip patch antennas (MPAs) are compact and easy-to-fabricate antennas, widely used in long-distance communications. MPAs are commonly fabricated using subtractive methods such as photolithographic etching of metals previously deposited using sputtering or evaporation. Despite being an established technique, subtractive manufacturing requires various process steps and generates material waste. Additive manufacturing (AM) techniques instead allow optimal use of material, besides enabling rapid prototyping. AM methods are thus especially interesting for the fabrication of electronic components
such as MPAs. AM methods include both 2D and 3D techniques, which can also be combined to embed components within 3D-printed enclosures, protecting them from hazards and/or developing haptic interfaces. In this work, we exploit the combination of 2D and 3D printing AM techniques to realize three MPA configurations: flat, curved (at 45°), and embedded. First, the MPAs were designed and simulated at 2.3 GHz with a -16.25 dB S11 value. Then, the MPA dielectric substrate was 3D-printed using polylactic acid via fused deposition modeling, while the antenna material (conductive silver ink) was deposited using three different AM methods: screen printing, water transfer, and syringe-based injection. The fabricated MPAs were fully operational between 2.2 to 2.4 GHz, with the flat MPA having a higher S11 peak value compared to the curved and embedded MPAs. Development of such AM MPAs in various configurations demonstrated in this work can enable rapid development of long-range antennas for novel applications in e.g., aerospace and Internet of Things (IoT) sectors.