A Low-Loss Sub-THz Radial Power Divider Based on Circularly Polarized TE₁₁ Mode

In this article, a 12-way radial power divider at sub-THz frequencies has been presented. The radial divider is based on circularly polarized TE<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{TE}_{{11}}^{\text{CP}}$</tex-math></inline-formula>) mode and features low insertion loss. By simplifying the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{TE}_{{11}}^{\text{CP}}$</tex-math></inline-formula>-mode transducer and minimizing waveguide flanges, the diameter of the power divider has been reduced to only 28 mm with a height of 17.35 mm. The measured insertion loss averages only 0.3 dB in the frequency range of 209–231 GHz. The isolation between the output ports almost always exceeds 10 dB, and the input return loss is better than 17.8 dB.