Numerical Simulation Of Beam-wave Interaction For Gyro-ampliifer

As one of the most important High-power millimeter-wave amplifier, gyro-amplifiers(gyroklystron and gyro-TWT) have been paid a great attention because of its merits ofhigh efficiency, high power, high gain and suitable bandwidth. It can be used as themost important millimeter-wave sources for communication, radar, electronic warfareand high-power microwave weapons. Numerical simulations of the beam-waveinteraction for gyro-amplifier play an important role as they can accurately predictnonlinear effects that dominate the behavior of the device (e.g., output power, efficiencyand bandwidth). The author began research on the beam-wave interaction forgyro-amplifier by the support of the national11thFive-Year plan and the Chinese hi-techdevelopment.Based on the nonlinear self-consistent theory, the numerical calculation of thebeam-wave interaction for gyro-amplifier has been studied in detail. Two parameternumerical calculation codes including the description of the electromagnetic fields and aself-consistent analysis of the electrons for gyro-amplifier are successfully designed andthe corresponding software implementations are achieved using Fortran language. Theyhave filled our country blank and made up an absence of the copyright of some otherexcellent codes, such as MAGY and MAGYKL. They also provide an importantcalculation tool for the design of gyro-amplifiers in our country.The main work made in this paper is below:1. Study on the numerical calculation of the high frequency characteristics of agyroklystron has been made in detail. The rules of the high frequencycharacteristics of the corresponding cavity with the structure parameters areanalyzed. This establishes prerequisites for the design of the high frequencystructure and the numerical calculation of the beam-wave interaction.2. Two forms of the transient electromagnetic field equation for the gyroklystronare deduced in detail. The numerical calculation model of speedspread isestablished in detail. The theoretical model and the research method of thebeam-wave interaction in input cavity, idler cavity and output cavity are distinctly investigated for the first time. They provide a solid theoretical basisand a complete system frame for the calculation code of beam-waveinteraction.3. The calculation model and flow process chart are studied in detail. Acalculation code of the beam-wave interaction for gyroklystron is successfullydesigned and the corresponding software implementation is achieved usingFortran language. When the speedspread is5%, the numerical results arecompared with the experimental datas, which shows that good agreements areobtained.4. Based on the Electron Cyclotron Resonance Maser dispersion equation and theactive wave equations, study on the numerical calculation of the linear and thenonlinear theory has been made in detail. A calculation code of the beam-waveinteraction for Gyro-TWT is successfully designed using Fortran language. Apreliminary model of the beam-wave interaction for a W-band Gyro-TWT isgiven and analyzed using the above code. The code provides a fast method forcalculating the optimal interaction length, gain and the saturated output power.