DESIGN OF A 1-MW, CW COAXIAL GYROTRON WITH 2 GAUSSIAN-BEAM OUTPUTS

The design of a 170 GHz, 1 MW-CW gyrotron for electron cyclotron heati ng of nuclear fusion plasmas is presented. The designed gyrotron incor porates a coaxial cavity to reduce mode competition, and a coaxial ele ctron gun to support the cavity inner conductor. A new mode converter splits the generated wave into two beams and radiates them in differen t directions. The radiated beams are transmitted to two output windows through two mirror systems, being transformed into Gaussian-like beam s. A single-stage depressed collector improves the overall efficiency of the gyrotron and reduces the heat flux to the collector surface.