Optimal Design Of Helix Traveling Wave Tube

Helix Traveling Wave Tube (TWT) is widely used in radar, airborne or ground-based communications, electronic warfare in military and commercial system because of its features of wide bandwidth and high-power.In this paper, each component of the helix TWT is presented. The theories, mechanisms and the Optimization of each subsystem are discussed. The main context focuses on the following aspects:The basic structure of the electron gun and the work status is summarized, and this paper gives the general steps in designing the electron gun. The definition of the cathode half-cone angle(CHCA) of initial value is amended to improve the initial design accuracy of the electron gun and shorten the design and optimization of time. The electron gun injection current, injection waist radius, waist location of injection parameters are calculated by using EOS(i.e. Electron Optical Simulator).The analysis, including cold-test calculations, for helical slow-wave structure has been a long standing problem within the TWT industry. Cold-test parameter is the premise of the beam and wave interaction calculation. Using high-frequency electromagnetism code HFSS,HFCS, the cold-test data is computed, and the data can guide the actual tube. HFCS calculates helical slow-wave structure with the high-frequency characteristics of data processing automation, computing speed and high precision.The theory of helix TWT beam-wave interaction has been study since TWT was developed. The beam-wave interaction analytical method is complex and not easy to calculate the parameters. BWIS is a simulator to calculate the beam-wave interaction. In this paper, the output characteristics of TWT with uniform pitch slow-wave structure are calculated by BWIS, including its output power and electronic efficiency. On this basis, starting from the electronic cluster parameters, the Dynamic velocity taper and the performance in improving output implications are studied. The result for the actual TWT propose a new scheme.Collector is an essential part of TWT, a system component collecting the electrons. Collector has been optimized using electron optical simulator, EOS in several aspects: adjusting the voltage, changing the collector radius, increasing the magnetic field values, adjusting the location of collector, inclusion of non-symmetrical slope, etc.. The methods provide a reference in improving the collector efficiency.