YuLu Hu

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.

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).

A 3-D Large-Signal Model of Folded-Waveguide TWTs

A steady-state 3-D large-signal model of the beam-wave interaction (BWI) in folded-waveguide (FW) traveling-wave tubes (TWTs) has been developed. The model used a three-port network representation of the circuit and a set of discrete rays representation of the 3-D electron beam. Values of the impedance elements that characterize the model are determined by a 3-D finite-element code, high-frequency circuit simulator (HFCS). Besides, the RF fields inside the beam tunnel are represented with the digitized field profile obtained from HFCS. A new circuit attenuation model is described by introducing only one parameter. The model has been implemented in the BWISFW-3-D code. The results of the code predictions agree well with the measured data for an FW-TWT operating in the W-band. The effect of uniform focusing magnetic field on BWI is also studied.

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.

Magnetic Focusing Simulator: A 3-D Finite-Element Permanent-Magnet Focusing System Design Tool

This paper reports the development of a 3-D finite-element design tool for the design of permanent-magnet focusing system called the magnetic focusing simulator (MFS). It is a new module of microwave-tube simulator suite developed by the University of Electronic Science and Technology of China. MFS specifically targets problem classes including periodic permanent magnet, wiggler, permanent-magnet quadrupoles, periodic cusped magnet, and so on. MFS is a finite-element code of magnetic scalar potential and is a solver of magnetostatic field. It can be used for designing, optimizing, testing, and validating the permanent-magnetic focusing systems. The theory of MFS is discussed in detail in this paper. Besides, the accuracy is compared with the commercial software ANSYS Maxwell, and the performance of MFS is also shown.

A three-dimensional nonlinear beam–wave interaction theory for common traveling wave tubes

A three-dimensional (3-D) nonlinear theory model of beam–wave interaction for common traveling wave tubes (TWTs) is described. The equation governing the amplitude of electromagnetic wave is derived analogously to Poynting’s theorem. The electron dynamics are treated using the 3-D Lorentz force equations. RF space charge fields are obtained from solutions of the Helmholtz equations. In the model, the RF field profiles for cold structure are represented by the digitized RF field calculated by a finite-element software, HFSS. Because the digitized RF field can be obtained in the same way, the 3-D simulation code can be used to simulate common TWTs, such as helix TWTs, coupled-cavity TWTs, and even the folded waveguide TWTs. Results from the 3-D code are compared with those from 1-D code, experiment and the existing analytical theories for three types of slow wave structures.