High-Power Broadband Multiple-Beam Klystron Circuit Development

The proposed program is for the development of a fundamental-mode S-band multiple-beam klystron (MBK) circuit and collector compatible with an eighteen-beam electron gun presently under development. The feasibility of the circuit to operate as a broadband high-power amplifying component when used in conjunction with the eighteen-beam gun (41.6 A at 42 kV) has been conclusively establish under the Phase-I program. Under the Phase-II program, the major objectives are to fabricate and integrate, in collaboration with our industrial partner, the circuit with the gun and collector into a high-average-power compatible MBK and to characterize and demonstrate the full capability and functionality of the MBK as a potential RF sources for advanced radar applications. The program structure and approach to be undertaken in this proposed effort are designed to parallel the same development path for the successful eight-beam MBK, which is the first fundamental-mode MBK developed in the United States and is presently under operation at the Naval Research Laboratory. In addition, we propose to perform a study to investigate the feasibility of utilizing multi-stage depressed collectors in future broadband high-power MBKs. If feasible, such a collector can greatly improve the overall amplifier efficiency and substantial reduce cooling requirement of future multiple-beam amplifiers.