Practical design of helix traveling wave tubes based on field analysis

Summary form only given. A novel method is presented for the design of helix traveling wave tubes (TWT) that is based on the linear field analysis of the coupled beam-wave system. The analysis is carried out by matching radial admittances at boundaries. This approach provides flexibility in treating multiple beam and circuit configurations with relative ease and simplifies the computer programming task. Solid or hollow beams are included, with or without a conducting cylinder on the axis. The results of the TWT field analysis has been compared with the conventional coupled-mode Pierce theory. The dispersion and axial power flow for the circuit without the beam, and therefore the various Pierce design parameters, are readily determined from the field analysis.