Design of A Ku-band orthomode transducer

An orthomode transducer (OMT) working in Ku band is presented in this paper. Its vertical polarization and horizontal polarization ports both use standard waveguide dimensions. The size of the branch end waveguide interface (straight or coupling) is $a_{11}=15.799mm, b_{11}=7.898mm$ (BJ140), and the common waveguide uses a circular waveguide with a radius of $R_{1}=8mm$. In order to simplify the structure and avoid the use of power combining structure at the coupling port, the physical three-port design of a single branch waveguide is adopted, and the multi-section conversion of the straight-through port and the coupling port screw tuning are adopted. Its VSWR is less than 1.4 while working in the Ku-band (12-15.7GHz). Besides, its fractional bandwidth reached 26.7% and achieving a broadband effect. Its VSWR is less than 1.4 while working in the Ku-band (12-15.7GHz). Besides, its fractional bandwidth reached 26.7% and achieved a broadband effect.