A wideband 8-way radial divider/combiner with stepped impedance transformers in ka band

A wideband 8-way radial divider/combiner with stepped impedance transformers in ka band is put forward in this paper. Simulation results show that return loss is below −20 dB between 29.4 GHz and 39.2 GHz for a single 8-way power divider; return loss is below −20 dB and insertion loss is better than −0.2 dB for an 8-way power divider/combiner including waveguide/microstrip transitions and microstrip/waveguide transitions from 31.8 GHz to 38.3 GHz.