Design of G-band Radial Power Combiner

In this paper, a G-band radial power combiner based on circular waveguide TM01 mode is presented. The proposed terahertz (THz) radial power combiner is constructed by a rectangular waveguide TE10 mode to circular waveguide TM01 mode transducer and a circular waveguide 1-to-10 channel radial power divider. To simplify the G-band radial power combiner design procedure, the mode transducer and 1-to-10 channel radial power divider are simulated separately. The THz radial power combiner simulation results tell that the back-to-back insertion loss is about 1.37 dB, and the return loss is greater than -18.3 dB in 170.6 similar to 186 GHz. Finally, the THz radial power combiner is fabricated by computer numerical control (CNC) milling and measured by G-band vector network analyzer. The back-to-back measurement results tell that the return loss of the THz radial power combiner is mostly greater than 10 dB, the typical value of the combining efficiency is about 75% in 170 similar to 185 GHz.