Wideband OMT with Modified Bøifot Layout and Co-aligned Waveguide Outputs

Paper in proceeding, 2024

We present the design of an orthomode transducer, OMT, that aims for the frequency band 210 - 375 GHz. The OMT employs a modified Bøifot layout. The OMT is optimized to fit into the tight spatial constraints, e.g., of the ALMA cartridge and harmonizes the receiver cartridge components for both polarizations by allowing use of the same configuration and components in both polarization chains. The OMT features a built-in novel broadband 90-degree waveguide twist, which minimizes the insertion loss by removing the H-split waveguide while eases receiver components integration with the 2SB mixers in the ALMA cartridge. The OMT was designed and optimized using HFSS™ 3D simulation software and tested with Keysight PNA-X VNA and three VNA extensions WR5.1, WR3.4 and WR2.2 in order to cover ultra-broad RF band.