Relativistic Klystron Amplifiers Driven by Modulated Intense Relativistic Electron Beams
Abstract
This paper, gives an overview of the novel relativistic klystron amplifiers which are driven by an annular intense relativistic electron beam (500 kV, 10 kA range) which is modulated by an external rf source (1.3 GHz, 100 kW range). Experiments, theory, simulation and simple models are presented to illustrate the unusual properties of such devices, which result from the intense space charge of the beam. Chief among them include electrostatic insulation against vacuum breakdown at high power levels, efficient current modulation, short bunching length, and amplitude and phase stability of the output signal. Many of these unexpected features were revealed in two separate experiments: one with the lower current beam (5 kA, 2 cm beam radius), and the other one with a higher current beam (16 kA, 6.6 cm beam radius). Three gigawatts or rf power at 1.3 GHz were generated with the large diameter beam at an efficiency of 35 percent with 37 dB gain. These experiments will be reviewed, along with a combination of particle simulation results and analytic models which facilitate the interpretation. Pay special attention to the unfamiliar features of these amplifiers, and shall address the critical issues which need to be solved before such amplifiers can fulfill their potential in a wide range of applications. Keywords: High power microwaves; Relativistic klystron amplifiers; Intense beam modulation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 11, 1990
- Accession Number
- ADA221075
Entities
People
- Jonathan F. Krall
- Michael A. Friedman
- V. Serlin
- Yueying Lau
Organizations
- United States Naval Research Laboratory