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Low noise static charging with the MAGIC electromagnetic FDTD PIC code is demonstrated to nanoamp levels. Unwanted currents in a small chamber resulting from necessarily rapid simulated precharging are damped by an elegant solution of simply overlaying the simulated experiment geometry with a time-dependent magnetic conductivity.
In this paper the possible paths for growing the impact energy of primary electron are considered. In this paper the simulation of process of secondary emission multiplication for different curvature of the electrodes in the cold secondary emission cathode crossed-field guns is considered.
Optimizing coupled-cavity traveling-wave tube (CCTWT) beam wave interaction (BWI) efficiency through tapering of the phase velocity could greatly increase RF output power. In order to do this work, a programme for CCTWT has been developed and implemented in BVERI. The programme could do multidimensional large-signal calculation of CCTWT and optimize the lengths of the individual cavities using simulated...
We present data showing the differences in modulation of the solid beam klystron and the HBK. Simulation results showing bandwidth and RF output power vs. RF input power was presented.
Under the condition of the solenoid focusing magnetic fields, Diocotron instability easily forms in the sheet electron beam, which could lead to collapse in beam propagation. This formation of Diocotron instability is presented in detail in this paper by using a three dimensional (3D) particle-in-cell (PIC) simulation. Then the Wiggler field is used to focus sheet electron beam, and the simulation...
This paper shows how the properties of cylindrically symmetrical klystron cavities can be computed quickly and accurately using the method of moments. The method can be used to benchmark results obtained using computer codes based on the discretisation of the volume of the cavity.
Simulation of a two-cascade design of the oscillator on a high-current relativistic beam with electrodynamic system as a section of a hollow cylindrical waveguide from which two sides resonant grooves are located is executed. It is shown, that in such design the feedback on reflected E01-wave is provided and the regime of oscillation from efficiency up to 20 % is possible.
This paper deals with the study of conical convergent electron gun for X-band linear accelerator tube in which the shapes of electrodes are determined with the help of finite element and iterative techniques, whereas, the output parameters are determined with the help of analytical technique. For the application of finite element method, the functional is calculated with the help of Poissonpsilas...
Vacuum electronics play a large and expanding role in communication and broadcasting networks. It is well known that TWTs are commonly used in satellite downlink transmitters because of their high efficiency and low weight. But vacuum electronics are also essential to many forms of earth-based communications. Uplink satellite stations use TWTs, EIKs, CCTWTs and Klystrons to provide communications...
It is shown, that in coaxial gyroklinotron the averages all over the wide electron beam (EB) efficiency reaches to 55% at optimized inclination angle of ring resonator about the axis of design and tubular EB. The design of coaxial gyroklinotron-klystron and gyroklinotron-TWT had been proposed.
In this paper, DTI will describe its recent efforts in the design of a compact, 300 kW, 1.5 ms amplifier for pulsed superconducting accelerators. Due to its unique design, the amplifier has applications to a wide range of accelerator technologies.
Inductive output tubes (IOTs) employ emission gating to modulate the electron beam directly at the cathode surface. The high efficiency of these compact devices has motivated their use in UHF television broadcast and particle accelerators. The instantaneous bandwidth of broadcast IOTs is two percent (6 MHz). Many radar and communications applications - in which the linearity and efficiency of the...
Next generation vacuum electron devices under development for millimeter and sub-millimeter wavelengths are often characterized by very small features that must be very precisely designed and manufactured for proper tube function and longevity. In this regime the need for automated physics-based optimization to aid the designer in meeting device performance specifications is much more critical than...
Calabazas Creek Research, Inc. (CCR) has included a nonlinear magnetostatic vector finite-element solver in its trajectory and particle-in-cell (PIC) code, Beam Optics Analyzer. With its seamless integration and intuitive graphical user interface, the new 3D magnetostatic field solver in BOA will help to design electron guns with complex coil geometries and high power beams that generate self magnetic...
We present results of modelling and details of fabrication of a pulse gyrotron to produce powers up to 10 kW peak and 10 W average at frequencies from 600 GHz to 2 THz. The gyrotron uses a pulse magnet that generates fields to 40 Tesla.
Efficient lightweight microwave power modules produce high RF output power in a compact package. Microwave power modules (MPM) are the first choice for rugged applications where reliability, efficiency and high power to weight ratio equipment is needed to perform in advanced applications such as high data rate communication and mobile synthetic aperture radars. L-3 Communications Electron Devices...
Over the last two years, Thales Electron Devices (TED) has developed and industrialized a new generation of microwave power module (MPM). This generation has been designed for military applications such as data link, radars (illuminators or weather radars) and electronic warfare (EW) systems. TED has designed the MPM to be modular. Depending on the future system needs, the MPM can be reconfigured...
This paper deals with the study of pillbox type RF window for X-band frequency, which is capable of handling peak and average powers of 2 MW and 2 kW, respectively at spot frequency 9.3 GHz with VSWR and insertion loss of 1.1 and 0.1 dB, respectively. The HFSS software is used for computation of diameter and thickness of ceramic and other required parameters.
A complete microwave characterization of the small-signal properties in terms of S-parameters behaviors of a flip-chip triode geometry device has been studied with CST simulator. The simulation results of a single triode and 10times10 triode array have been proposed.
The transmission characteristic of a one-dimensional array of rectangular holes was examined experimentally at X-band. The resulting frequency response of transmission was found to be dependent on frequency and periodicity of the structure.
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