A three-dimensional model of the double-slot coupled cavity slow-wave structure（CCSWS） with a solid round electron beam for the beam–wave interaction is presented. Based on the "cold" dispersion, the "hot" dispersion equation is derived with the Maxwell equations by using the variable separation method and the field-matching method. Through numerical calculations, the effects of the electron beam parameters and the staggered angle between adjacent walls on the linear gain are analyzed.

A theoretical model was presented for the double slot coupled cavity slow-wave structure (CCSWS) with arbitrary staggered angle between two adjacent walls in an abstract published by the authors in last year's IVEC. In this abstract, this model is validated by comparing its results of two typical structures, one operating in Ka-band with in-line slots and the other operating in X-band with staggered slots, with those obtained by the equivalent circuit model, the simulation software Ansoft HFSS code and the experimental data.

Based on a sheet electron beam propagating through the tunnel of a staggered double-grating arrays waveguide (SDGAW) slow-wave structure (SWS), a three dimensional linear theory for describing beam-wave interaction is presented, in which the higher order terms inside the groove were retained. With the optimized parameters, a 1THz SDGAW Cerenkov traveling wave amplifier (CTWA) may obtain a moderate net gain larger than 10dB/cm in 0.92THz to 1.145THz considering the serious Ohmic losses in THz frequency range.

A three dimensional (3D) linear theoretical modal for a sine waveguide sheet beam travelling wave tube is developed based on the field matching method. The dispersion curve for a 0.22THz sine waveguide slow wave structure is given. The effects of the beam parameters on the beam-wave interaction are discussed.

A 3-D model of the double slot coupled cavity slow-wave structure (CCSWS) with a solid round electron beam for the beam-wave interaction is proposed in this abstract. Based on the "cold" dispersion, the "hot" dispersion equation is derived with the Borgnis potential function by using the field-matching method. Then, the formula of the linear gain is given.

A theoretical model for the arbitrarily-shaped groove staggered double-grating array waveguide (SDGAW) slow-wave structure (SWS) is used to calculate the characteristics of dispersion and coupling impedance for a step-shaped staggered double-grating slow wave structure for W band TWT application. The results are compared with those obtained by CST-MWS code simulation.

This abstract discussed the modification of an equivalent circuit model of double-slot coupled cavity slow wave structure (CCSWS), including in-line and staggered with overlap ones. The model was investigated by comparing its calculation results of high frequency characteristics for a relative structure in X-band, with those obtained by full-wave electromagnetic software HFSS.

An analytical model is presented for the double slot coupled cavity slow-wave structure (CCSWS) in this abstract. By matching boundary conditions in conjunction with Green's function techniques and moment method (MOM), the formulae for discussing the high frequency characteristics of the SWS, including dispersion and coupling impedance, are given.