3D Metal Printed Broadband X-Band Septum Polarizer

An X-Band septum polarizer covering the International Telecommunication Union (ITU) Deep Space and Near Space Bands was fabricated using 3D metal printing. The polarizer was implemented using a series of stepped septums, with rectangular waveguide input ports and a circular waveguide output port. The A6061 RAM-2 aluminum alloy was used in the 3D printing process due to its smooth surface finish when compared with similar aluminum alloys. The polarizer's performance was tested as part of a horn antenna assembly in a compact antenna range. The measured cross-polarization was better than 20 dB over a wide frequency range of around 7 GHz to 8.8 GHz.