On the Utility of 3D Printing for Rapid Prototyping Wideband Arrays for RCS Measurements

The utility of 3D printing as applied to wideband arrays for radar cross section (RCS) characterization is demonstrated. Specifically, a combination of stereolithography and copper plating is used to fabricate eight-element linear and circular arrays. The individual antenna elements are built in two parts, which are joined with liquid resin and then cured in a custom ultraviolet chamber. The geometry designed for 3D printing without compromising the radio frequency (RF) performance includes curved and internal concave surfaces, acute joints, and interior walls. Reflection coefficient and RCS are measured using a custom RCS range. Good agreement between measurements and simulations for both impedance and radiation characteristics demonstrates the suitability of 3D printing for rapid prototyping for this and similar RF applications.