Additive Manufacturing of Antennas for Expendable and Low-Cost UAS Applications

In this paper, we will present a low-cost solution for printing directive antennas. The motivation for this work is the integration of antenna systems into low-cost and expendable unmanned aerial systems (UAS) platforms. With the use of consumer grade fused deposition modeling (FDM) and copper electroplating, replicas of a tapered waveguide and a dual-ridged horn antenna were fabricated to test the overall concept. Electrical measurements of the additively manufactured (AM) antennas show comparable bandwidth properties, but with some loss in gain. Two curved dual-ridged horn antennas are designed by projecting the tapered ridge profile onto an exponential surface to either reduce the overall height or increase the antenna length within the original profile. Simulations show that both designs maintained the >6 GHz bandwidth exhibited by the baseline antenna, and one of the designs provides gain comparable to the baseline horn antenna. This antenna was fabricated, measured, and its integration into a representative small UAS wing was simulated. While the bandwidth was maintained, gain losses on the order of 1.5 dB were observed across higher portions of the frequency spectrum. Overall, the results are encouraging and motivate further examination into AM antenna applications.