A High-Power Single Rectangular Grating Sheet Electron Beam Traveling-Wave Tube

In this paper, a high-power Ka-band traveling-wave tube (TWT) driven by a sheet electron beam is proposed and demonstrated by means of the simulation and experimental methods. The single grating rectangular waveguide with large width-to-height ratio is used as the slow-wave structure (SWS). An
$E$
-plane bend energy coupler is put forward to feed this wide SWS. An irregular transition structure between the input waveguide and the SWS is suggested and designed, which is beneficial to suppress the self-excited oscillation. For a practical electron beam (20 mm
$\times \,\, 1$
mm, 150.1 kV, 850 A, and 20-ns), the output power of this single rectangular grating sheet beam TWT is larger than 750 kW from 34.5 to 35.4 GHz. The maximum power is 1.21 MW at 35 GHz, corresponding to a gain of 20.4 dB.