| Traveling wave tubes(TWTs) are broadband, high power, high gain microwave/millimeterwave amplifiers, which, taking an irreplaceable role in modern military electronic equipment, are widely used in communications, electronic warfare and radar systems. However, manufacture of TWTs is quite complicated involved in many disciplines, such as electronic optics, magnetics, cathode electronics, microwave electronics, electromagnetic fields theory, materials, mechanics and pyrology. The technologies on TWTs have been making great progress with developments and applications of computers, which, enhancing design abilities, reducing production periods, decreasing hardware experiments, improving performance, solidifying known experiences, all of these are deeply dependent on. CAD has become a key technology in producing TWTs.It is higher demand for high power microwave resource, when modern electronic warfare, broadband high power array radar system, high power jammer and microwave weapon are developed fast. Broadband high power devices are main research object. Power synthesize technique is main method gained broadband high power microwave resource, high power broadband TWTs as array unit end amplifier, because of the conflict between broadband and high power.Traveling wave tube gain and phase matched operation (TWTGPM) is key device in power synthesize technique. The design and manufacture of TWTGMP is very difficult, because of higher performance demand. The low of finished product ratio is serious difficult for domestic manufactory.Experts suggest that CAD is a key technology in designing and producing TWTGPM, after broad demonstration. High intensity simulation can advance design capability effectively, before manufacturing.Chapter I introduce the advance, problem and future of microwave tube CAD technology. Numerical methods for microwave tube CAD are described. Large electromagnetism (EM) analyzing software are enumerated. The CAD software of microwave tube component are character. MMACE project of America and TWTCAD project of China are presented. Advances of TWTGPM are present. It is fundament of this research work.Chapter II analyzed main factors of causing the dispersion and coupling impedanceof TWTGPM variation based on the slow wave circuit. The visualization computing software is developed. The software is used to determine the effect on dispersion and on-axis interaction impedance of several helical slow-wave circuit parameter variations, including thickness and relative dielectric constant of the support rods, pitch width, height of the metal vane and helix average radius. The dispersion and impedance are compared for each set of variations. Based on this kind of information, manufacturers can conduct cost-benefit analyses of their manufacturing tolerances and optimize designs for a wide variety of devices before fabrication.Chapter III introduce the method of particle in cell(PIC). Three dimensional(3D) nonlinear theory of TWT is developed, include fundamental RF and harmonic interaction, period permanence magnetic filed and uniformity magnetic field. It can be degenerated to 1-D, 2-D and 3-D Rowe theory based on equivalent circuit model. Super particle model is used to compute the 3-D space charge forces based on PIC. Effect of electric field sinking is considered.Chapter IV explored the application of Object-Oriented(OO) software engineering methodology in large scientific research software development. A TWT-CAD software architecture is given for 3-D beam-wave nonlinear interaction, coding by Microsoft Visual C++6.0, integrating OO software engineering methodology and ViSC (Visuali- zation in Scientific Computing).Chapter V present advance, difficult of design and manufacture, and counter- measure of TWTGPM. A network computing plat, analyzing gain and phase characteristic of TWTGPM, is built, integrating OO software engineering methodology, ViSC and network parallel computing, coding by Microsoft Visual C++6.0. It is a feasible framework, to be used to analyze gain and phas...
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