Additive manufacturing of low cost and efficient proof of concepts for microwave passive components

A study on the passive microwave components made by polymer additive manufacturing (polymer jetting) is presented. Different types of components (waveguides, couplers, power dividers, filters and antennas) are designed to be made in a single part. Using a simple and cost-effective metallisation by applying silver paint, various prototypes with complex geometries have been manufactured to evaluate these proofs of concept and the robustness of the low-cost approach to make microwave components. Different measurements show that the obtained filters can provide an acceptable unloaded Q factor of 400–500 for the operating frequencies of 12–22 GHz. Waveguiding structures such as a mode converter, which is used as a broadband antenna, have also notably efficiently worked up to the Ka band (36 GHz). Due to a remarkable accuracy of nearly 80 µm, the obtained results of the proposed coupler, power divider and antennas are consistent with the full wave simulations, which prove that the currently available three-dimensional plastic printers can provide notably accurate prototypes to design original components.