Optimization Design Of Ultra-wideband High-power Traveling Wave Tube

Since Kompfner invented the Traveling Wave Tube in 1943, Traveling Wave Tubes have been playing more and more important role in people's life. For its advantage in high power output, Traveling Wave Tubes are widely used in communication, military affairs, especially in the field of electronic countermeasure. Helix Traveling Wave Tubes and coupled-cavity Traveling Wave Tubes are the most popular instruments in Traveling Wave Tubes, helix Traveling Wave Tubes are widely used in broad band Traveling Wave Tube for its smooth dispersion characteristic, while coupled-cavity Traveling Wave Tubes are widely used in high power occasion for its unique slow wave structure. The design of super broad band and high power Traveling Wave Tube of the paper chooses the helix as its slow structure, the software of Microwave Tube Simulator Suit is used to finish the design and simulation of electron gun, high frequency structure, beam-wave interaction region and collector of the broad band and high power Traveling Wave Tube whose frequency band is between 2GHz and 7.5GHz. The major job of the paper includes these aspects:First, from the aspect of optimizing the structure and widening the bandwidth of the Traveling Wave Tube, the module of Electron Optics Simulator of Microwave Tube Simulator Suit is used to modeling and calculate the electron gun of broad band and high power Traveling Wave Tube, the cathode current and radius of electron beam are useful for the parameter setting of beam-wave interaction region.Second, in order to smooth the dispersion curve and augment the coupling impedance of Traveling Wave Tube, the module of High Frequency Circuit Simulator of Microwave Tube Simulator Suit is used to modeling and calculate the high frequency structure. Newly and rectangle clamps are used in the high frequency structure, which reduces the contact area and heat loss between helix and clamps. The dispersion curve gets smoothed and the bandwidth gets augmented, thus, the design of high frequency structure has been finished.Third, in order to suppress harmonic and enhance output power, the module of Beam Wave Interaction Simulator of Microwave Tube Simulator Suit is used to design and simulate the interaction region of super broad band Traveling Wave Tube. The way of cut-off and attenuator are used to suppress backward wave and prohibit oscillation, the application of technique of pitch jumping not only suppresses the harmonic but also enhances the output power, which satisfies the requirement of huge output power.Forth, from the angle of increasing the efficient of Traveling Wave Tube and avoiding the waste of resource, the module of Electron Optics Simulator of Microwave Tube Simulator Suit is used to modeling and calculate the collector of Traveling Wave Tube. The application of technique of step-down collector makes good use of electron beam abandoned, which increases the efficient of collector of Traveling Wave Tube. Suitable setting of collector voltage decreases the efficient of back flow, which saves the energy and avoids the waste of resource of the world.Fifth, for the reason that our work team has good relationship with Chengdu GuoGuang Electric Co., Ltd, all the model data and measurement data related to electron gun, high frequency structure, interaction region and collector of Traveling Wave Tube come from it. Under the cooperation between our work team and Chengdu GuoGuang Electric Co., Ltd, several completed products of the Traveling Wave Tube have been made and they have been used in the market, which highly validates the reasonableness and feasibility of the design of super broad band and high power Traveling Wave Tube.