3D metal printed Ku/Ka Band modified turnstile junction Orthomode Transducer

Orthomode Transducers (OMTs) are key components in dual-polarized satellite communication systems. Turnstile junction (TJ) OMTs are widely popular since their structural symmetry suppresses the undesired higher order modes, which degrade impedance matching and isolation of the OMT. Several works on TJ OMTs operating in single (or narrow) frequency band have been published. In contrast, this paper presents a modified TJ OMT designed for multiple frequency bands: Ku-Band (10.7 GHz-12.75 GHz), lower Ka-Band (19.5 GHz-20.5 GHz) and upper Ka-Band (29.2 GHz-30.2 GHz). Unlike ordinary TJ OMT, the modified OMT besides discriminating the orthogonal polarization signals, also acts as a frequency diplexer. The OMT was manufactured using cost-effective 3D metal printing. The simulated and measured S-parameters were evaluated in Ku, lower and upper Ka bands. The OMT functionality was verified through field test measurement.