XiaoFang Zhu

Recent Developments to the Microwave Tube Simulator Suite

Recent developments to microwave tube simulator suite (MTSS) are reported in this paper. The MTSS is a full-featured tightly integrated software package for microwave tube analysis and design. It includes a commercial grade user interface and three physics simulators. The electron optics simulator is a finite-element (FE) 2-D and 3-D electrostatic steady-state beam trajectory code that has been used to design beam optics, including electron gun and collector. High-frequency circuit simulator is a full 3-D FE computational electromagnetic code that aims to get the accurate electromagnetic wave character spreading in high-frequency structures, such as dispersion, coupling impedance, and attenuation. Beam wave interaction simulator is a large-signal simulation code for helix traveling wave tubes (TWTs), coupled-cavity TWTs, and klystrons. The first version of MTSS was released in 2007, and all of these three physics simulators and user interface are improved and updated over the past six years. This paper reports on some significant advances to MTSS; new Ribbon style user interface, a lot of component modeling templates, more abundant postprocessing features, parallel version, full 64-bit version, more physics, and computation methods improvement.

Thermal Analysis of Novel Helix TWTs

Consider the thermal contact resistance and the thermal conductivity as the function of temperature, the power dissipation of BeO and diamond-supported, the diamond-studded and the full-diamond helical slow-wave structures (HSWS) are computed using ANSYS. Results indicated the studded-diamond circuit is better than the diamond-support circuit. Especially, the full diamond circuit demonstrated advantage of excellent heat removing

Accurate large signal analysis of a wideband helix TWT using Beam Wave Interaction Simulator

Using Beam Wave Interaction Simulator (BWIS), one module of Microwave Tube Simulator Suite (MTSS), a wideband helix TWT has been accurately simulated. The slow-wave circuit parameters are calculated by High Frequency Circuit Simulator.

High Frequency Circuit Simulator based on finite integration technology

This paper provides the design and realization of high frequency circuit simulator (HFCS) which is based on the Finite Integration Technology. For vilification, the cold-test characteristics of two actual helical slow wave structures have been calculated and the results were found to be consistent with those of MAFIA simulation with same mesh density.

Microwave Tube Simulator Suite-Part I: Architecture and Feature

Microwave tube simulator suite (MTSS), tools for microwave tube design, is developed by Theory and Computer Simulation Lab. of University of Electronic Science and Technology of China. It consists of four modules now, microwave tube design environment (MTDE), electron optics simulator (EOS), high frequency circuit simulator (HFCS), and beam-wave interaction simulator (BWIS).

Recent advances of MICROWAVE TUBE SIMULATOR SUITE

Microwave tube simulator suite (MTSS) is a fully featured software package for microwave tube analysis and design. it consists of four modules now, microwave tube design environment (MTDE), electron optics simulator (EOS), high frequency circuit simulator (HFCS), and beam-wave interaction simulator (BWIS).

Effect of Thermal strain in helical slow-wave circuit on TWT Cold-test characteristics

A simulated model has been established to calculate the temperature of helical slow-wave circuits accurately. The finite-element-method software ANSYS was used to analyze the thermal distortion of the traveling-wave-tube (TWT) helical slow-wave circuit. The thermal-analysis results show that the thermal stress deforms the helix primarily at the positions contacting the support rods and that the expansion of the helical tape width and thickness are very small and can be ignored. The effect of thermal strain on the helical slow-wave circuit cold-test characteristics was analyzed in detail. The periodic boundary conditions in the computer code MAFIA were employed to determine the effect on dispersion and on-axis interaction impedance. With increased helix temperature, the phase velocity decreases significantly, and the interaction impedance varies slightly.

A useful design technique of helix pitch profile for high efficiency TWTs

A useful design technique of helix pitch profile for high-efficiency Traveling-Wave tubes (TWTs) is put forward. The purpose of the design technique is to increase the normalized axial growth rate of ac electric field amplitude by selecting an appropriate helix pitch profile and so that the power and efficiency are maximized.

Application and validation of Microwave Tube Simulator Suite

Microwave Tube Simulator Suite (MTSS) is a full-featured software package for microwave tube analysis and design. It has been developed by University of Electronic Science and Technology of China (UESTC) and validated against some helix traveling wave tubes.

A one-dimensional large signal simulation of folded waveguide TWTs

A steady-state large signal model of the beam-wave interaction in a folded or serpentine waveguide traveling-wave tube is described. The model used a three-port network representation of the circuit and a 1-D disk model of the beam. Values of the admittance elements that characterize the model are identified with a 3-D finite element code, HFSS. This model can be used to simulate the beam-wave interaction in other types of slow-wave structures.