The Research Of High-power Gated Continuous Wave Travelling Wave Tube Self-oscillation Phenomenon

Traveling-wave tube(TWT) as a power microwave devices, has gone through decades of development. The TWT performance of different power and different bands has gained greatly improved, that makes TWT widely used in electronic warfare, radar and satellite communications, etc. electronic devices. L-band high-power TWT has important applications in electronic warfare weaponry. However, in practical applications, after the use of different output loads, the L-band traveling wave tube will be caused a problem of spiral seizure and burned repeatedly phenomenon. This situation has seriously affected the normal operation of electronic warfare devices that equip with such power microwave devices.For the self-excited oscillation problem of L-band high-power TWT in practical applications, this paper makes a detailed theoretical analysis from the following several aspects: electron motion in the electrostatic field, the influence of magnetic field on the electron motion, the impact of the electron injection layer flow characteristics of the electron gun design, the types of TWT self-excited oscillation, and the influence of the slow wave structure characteristics. According to the theoretical analysis, this paper provides a design improvement in the lumped attenuator and slow-wave tube circuit configuration of L-band high-power TWT, which can effectively suppress the backward wave oscillator of this kind of TWT, thereby preventing the self-excited oscillation from affecting the normal use of the device..The results loading experiment for new improved structure show the design not only meet the performance parameters such TWT, but also solve the problem of self-oscillation when connected to a different output load.