| High power millimeter wave vacuum electronic tubes have important application foreground at the fields of science research and military.The traditional vacuum electronic tubes, as traveling wave tube and klystron etc, have met huge troubles at the band of millimeter wave for the reason of limiting by the structure and mechanism. On the other hand, the laser,which is based on quanta effect, can’t work effectively at this wave band. But the gyrotron can product high pulse power and average power at this wave band. One of very important member in the gyrotron’s family is the gyroklystron amplifier, which has abilities of high gain; high efficiency; high power, is widely applied at the fields of millimeter wave radar, communication and other science research works.In this dissertation the key technology of the high power millimeter wave gyroklystron amplifier, including input system;high frequency cavities;output window; beam and wave interaction; hot test experiment, have been studied in detail.In the second chapter, the initial design schemes of the input window for the Ka band and W band gyroklystron amplifier have been given by using the theory of equivalent network. By using the3D software HFSS emulation, the precise design schemes of the wide-band input window have been made. At the same time, the approximately analysis model for the input coupler have been built. Through the calculation and HFSS emulation, the design parameters of the high mode purity input coupler for the Ka band and W band gyroklystron amplifier have been gotten.In the third chapter, the theory analysis of the high frequency cavities for gyroklystron amplifier has been described by using mode matching theory. Based on the theory analysis, the programs for input cavity, bunching cavity and output cavity are built. Through the calculation; HFSS emulation and cold test, the design parameters of the input cavity; bunching cavity and output cavity for the Ka band and W band gyroklystron amplifier have been gotten.In the fourth chapter, the theory analysis of the output window for gyroklystron amplifier has been described by using mode matching theory to build scattering matrix. Through the calculation;cold test experiment and HFSS emulation, the design parameters of the double disk output window for the Ka band and W band gyroklystron amplifier have been gotten. On the other hand, the thermal analysis of the output window has been accomplished. Through the thermal analysis, a new type of double disk output window with inter space cooling, which can increase the power capability of window, has been gotten.In the fifth chapter, nonlinear great signal theory has been described. The influences of electron parameters; input power; frequency; magnetic field and its profile, etc, on efficiency; bandwidth and output power have been studied.Based on the analysis and calculations of the gyroklystron amplifier’s self-consistent nonlinear theory, the schemes of Ka-band and W-band,TE01mode, four-cavity fundamental wave gyroklystron amplifier have been designed. On the other hand, the PIC model for Ka-band and W-band,TE01mode, four-cavity fundamental wave gyroklystron amplifier have been built according to the schemes. At the same time, the particles simulation has been achieved. The results of the PIC simulation are agree with the results of theory calculation.In the sixth chapter, the makeup and function of the hot test workbench have been introduced. At the same time, a sample of the gyroklystron amplifier is made and tested. The hot test experiment shows that the gyroklystron amplifier has produced301kW peak output power,6kW average power,39.1%efficiency and saturated gains of41.8dB at center frequency34GHz, with70KV,11A annular electron beam at a magnetic field of1.31T. The full width half maximum (FWHM) bandwidth is greater than280MHz. The amplifier is zero drive stable. Experimental results are found to be in excellent agreement with theoretical predictions. |
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