Abstract: A 16-channel equal power distribution power synthesizer is designed, which adopts radial power synthesis and is based on the E-plane sector waveguide. The overall size of the final design is 480.1 mm×457.7 mm×60.3 mm. Simulation and measurement results show that the power synthesizer operates in the frequency band of 5.2-5.9 GHz, with insertion loss of 0.5 dB and phase balance within 3 degrees for each channel. The synthesizer can withstand a maximum input peak power of 8000 W under the condition of air breakdown threshold, which meets the need of high-power synthesis and can be used in C-band solid-state transmitter-related applications.