Abstract: A radial waveguide spatial power combining technology is proposed to break through the low output power of single solid state device in the microwave and millimeter-wave bands,in terms of the axial symmetry of the dominant mode TM00 in the radial waveguide.A 32-way spatial power combining system with radial waveguide in X-band frequency is fabricated by the simulation of HFSS(high frequency structure simulator) and ADS(advanced design system) in the paper.Its insertion loss is below 1dB,reflection loss is b...