Chip-based antenna array from 3D printing: WSU showcases flexible wireless modules;

A research team led by Washington State University (WSU) reports in Nature Communications on a chip-based antenna array whose radiators were produced via 3D printing. The goal is a flexible, conformal radio architecture for applications in aerospace, automotive engineering, and wearable electronics. At the heart of the work is the combination of a compact, integrated processor for real-time corrections and a conductive ink based on copper nanoparticles that, through additive manufacturing, brings precise antenna geometries onto flexible substrates.

The authors address a well-known problem of conformal arrays: mechanical deformations and vibrations shift impedance and phase, leading to beam pattern errors.

“This proof-of-concept prototype paves the way for future smart textiles, drone or aircraft communications, edge sensing, and other rapidly evolving fields that require robust, flexible, and high-performance wireless systems”, said Sreeni Poolakkal, PhD student, School of Electrical Engineering and Computer Science, Washington State University.

For the metal prints, the team uses a copper-nanoparticle ink developed by partners at the University of Maryland and at Boeing.

“The ink is a very important part in additive, or 3D printing,” said Subhanshu Gupta, associate professor in the WSU School of Electrical Engineering and Computer Science and a co-author on the work. “The nanoparticle-based ink developed by our collaborators is actually very powerful in improving the performance for high-end communication circuits like what we’re doing.”

The printed structures remained electrically stable under bending as well as under exposure to humidity, temperature, and salt. A lightweight, energy-efficient 4-element array was demonstrated; as a tileable design, it could be scaled to 16 elements. Each array tile has its own processor and operates independently, which favors modular scaling.

“We used this processor that we developed to correct for these material deformities in the 3D-printed antenna, and it also corrects for any vibrations that we see,” said Gupta. “The ability to do that in real time makes it very attractive. We were able to achieve robust, real-time beam stabilization for the arrays, something that was not possible before.”

The project was funded in part by the Air Force Research Laboratory, the Washington Research Foundation, and the M.J. Murdock Charitable Trust Foundation. From an industry perspective, the results are relevant because 3D printing here not only provides design freedom, but also integrates electronics that compensate for the inevitable tolerances of conformal antennas during operation.