This paper describes the Virtual Prototype of a Dielectric Window (DW) for High Power Microwave Vacuum Tubes and Linear Accelerators (LINAC). Design formulas are provided and Computer Aided Design techniques based on COMSOL Multiphysics are proposed. The virtual prototype considers the Thermo-mechanical effects due to the joule effect induced by the power which crosses the DW and the Thermal co...

Understanding the interaction between a weakly ionized gas and a shock wave is important for detailed knowledge of the conditions of planetary atmospheric entry. This interaction can manifest itself in the form of a localized increase of electron temperature, plasma induced shock dispersion and acceleration, optical emission enhancement, or double electric layers. In our work, a microwave disch...

A simulation study to assess the potentiality of sea surface wind vector estimation based on the approximation of the forward model through Neural Networks and on the Bayesian theory of parameter estimation is presented. A polarimetric microwave radiometer has been considered and its observations have been simulated by means of the two scale model. To perform the simulations, the atmospheric an...

Recent work at the University of New Mexico (UNM) by Morelan~ et al. (1) has demonstrated how finite length effects in a high power vacuum backward wave oscillator (BWO) can be exploited to achieve frequency agility for constant beam and magnetic field parameters. This enhanced band~vidtll is obtained through the axial displacement of the slow wave structure with respect to the cutoff neck “inl...

Motivated by recent advances in wideband-gap (WBG) gallium nitride (GaN) semiconductor technology, there is considerable interest in developing efficient solidstate power amplifiers (SSPAs) as an alternative to the traveling-wave tube amplifier (TWTA) for space applications. This article documents the general architecture considerations pertinent to developing SSPA architectures that can enable...

Thermal deformation caused by Non-uniform temperature distribution in disk-loaded waveguide affects the resonant frequency of LINAC deeply. A new approach of multi-disciplinary integration is adopted to study the influence of the thermal deformation on the resonant frequency. The kernel technology is to simulate the thermal deformation of the accelerator tube loaded RF power via thermal-structu...

In the field of microwave hyperthermia, the use of minimally invasive applicators is recognized as a very promising technique for the treatment of small tumours because a very thin applicator can be easily introduced inside the body and precisely localized using the most advanced 3D imaging techniques and surgical robots. Minimally invasive hyperthermic applicators (MIHA) have been successfully...

The effects of electron-beam prebunching on the radiation buildup process in a free-electron maser oscillator operating in the frequency range of 4–5 GHz were studied. An electron beam of 10 keV, 1 A was prebunched by means of a microwave tube section, accelerated to 70 keV, transported through a drift region by a solenoidal magnetic field and injected into a linearly polarized wiggler in which...

Abstract BACKGROUND: In 1970, a report from the former Soviet Union described the "microwave syndrome" among military personnel, working with radio and radar equipment, who showed symptoms that included fatigue, dizziness, headaches, problems with concentration and memory, and sleep disturbances. Similar symptoms were found in the 1980s among Swedes working in front of cathode ray tube monitors...

Related Articles Oblique electron-cyclotron-emission radial and phase detector of rotating magnetic islands applied to alignment and modulation of electron-cyclotron-current-drive for neoclassical tearing mode stabilization Rev. Sci. Instrum. 83, 103507 (2012) 0.22 THz wideband sheet electron beam traveling wave tube amplifier: Cold test measurements and beam wave interaction analysis Phys. Pla...