3D Printed Waveguide Simulator for Rapid Verification of Asymmetric Unit Cells

A singly polarized asymmetric Vivaldi unit cell operating from 1 to 6 GHz is studied in regular and mirrored infinite environments. The element features an integrated coax-to-slotline balun and is realized at low-cost with digital light processing 3D printing. Simulations of the unit cell in a regular infinite array environment show good scanning performance with VSWR < 3 up to 60°. By contrast, simulations of the unit cell in a mirrored infinite array environment reveal impedance anomalies where the VSWR > 3. To demonstrate the resonances are physical and measurable, a 12-element waveguide simulator is fabricated, and the scan impedance measured at several scan angles. The results give insight into the behavior of tightly coupled elements in an infinite mirrored array environment while showing the utility of additive manufacturing to quickly test unit cell performance.