Analysis of W-band traveling-wave tube based upon slotted sine waveguide slow wave structure

Abstract

In this paper, a W-band traveling-wave tube (TWT) is proposed by combining the slotted sine waveguide (SSWG) slow-wave structure (SWS) with the cylindrical electron beam. The dispersion properties and interaction impedances of the SSWG SWS are analyzed by using the numerical simulation and compared to the conventional sine waveguide (SWG) SWS. The interaction impedances of the SSWG SWS are much higher than the SWG SWS over the entire operating frequency band. The whole high frequency system, which consists of the SSWG SWS, the coupler, and the attenuator, is designed suitably. From the particle-in-cell simulation results, the maximum output power of the SSWG TWT at the typical frequency of 94 GHz can reach 284.5 W with the cylindrical electron beam of 20.6 kV and 180 mA. Compared to the SWG TWT, the SSWG TWT possesses the higher beam–wave interaction efficiency and the shorter saturated tube length.