A Fully 3-D-Printing-Compatible E-Plane Elliptical Waveguide Junction for Power Dividing/Combining Applications

In this paper, a new class of 3-D-printing-compatible E-plane elliptical waveguide (EWG) junction is proposed for wideband power dividers/combiners. The junction is based on an EWG architecture with tailored power dividing and impedance-matching structures that are configured in a Y-shape profile. The junction is devised according to a specified orientation for 3-D printing and it features smooth and intrinsically self-supportable waveguide sidewalls. Compared to conventional rectangular waveguide junctions, the proposed EWG junction exhibits dramatically enhanced structural compatibility with additive manufacturing technology. A novel four-way EWG-junction-based power divider is demonstrated at Ka band. The power divider is prototyped monolithically by incorporating Polyjet 3-D printing and electroless copper plating processes. RF performance of the power divider shows a return loss of mostly over 20 dB, transmission coefficients of averagely −6.5 dB, and small amplitude and phase imbalances across the entire Ka band, successfully validating the wideband and low-loss characteristics of the proposed EWG junction.