Enhanced Features for Design of Traveling Wave Tubes Using CHRISTINE-1D

Traveling wave tubes (TWTs) are vacuum devices invented in the early 1940s for amplification of radio frequency power. These devices are critical for radar, communications, and electronic warfare missions in the military, as well as in commercial applications. The physics-based design and simulation code CHRISTINE-1D was used in the past to explore different TWT circuit designs and to automate the process of parameter estimation. However, the current capability of CHRISTINE-1D allows optimization of only helix TWT designs and includes a limited number of optimization goal functions. In addition, the current optimizer in CHRISTINE-1D employs a modified steepest descent method to carry out the optimization process. The objectives of this paper are threefold: (1) to investigate optimization techniques that may be better suited for this problem (for example, simplex type methods such as Nelder-Mead and Dividing Rectangles); (2) to allow optimization of nonhelix TWTs; and (3) to implement new optimization goal functions. Finally, to show the feasibility of our approach, we apply our optimization algorithms to the problem of designing a folded waveguide slow-wave circuit.