On the Design of a High-Efficiency Double-Beam Gyrotron

The gyrotron that operates with a double electron beam is designed and presented. The design of a 42-GHz 200-kW gyrotron at TE 03 mode has been done and presented elsewhere. To enhance the RF power without losing the interaction efficiency of the 42-GHz gyrotron, double electron beams are launched into the cavity. The beam-wave interaction calculations and power and frequency growth estimation are performed and compared with the single-beam operation results. In the design of the gyrotron, in-house developed codes, GCOMS, MIGSYN, and MIGANS, as well as commercially available codes MAGIC and EGUN are used. The results show that more than 400 kW of power is not possible by single-beam operation while the double-beam operation shows this amount of power with the same mode. To achieve the double electron beams of the desired parameters at the cavity region, the double-beam magnetron injection gun (MIG) is designed. The results of the interaction cavity and MIG show the feasibility of the double-beam gyrotron for high-power and high-efficiency operation.