Application of Additive Manufacturing Technologies for Realization of Multilayer Microstrip Directional Filter

In this paper, an application of additive manufacturing technologies for realization of multilayer microwave circuits in microstrip transmission line technique is presented for the first time. An example of a second-order cascaded loops directional filter allowing to separate 2100 MHz LTE band was designed in suspended microstrip with three metal layers, manufactured using a combination of PolyJet 3D printing with UV cured VeroWhitePlus polymer material and magnetron sputtering of copper, and assembled out of two parts using a "lego-like" process. The obtained results for the manufactured circuit confirmed that the proposed approach is of potential use for circuits and systems operating within the microwave frequency range.