Electromagnetic Waves in Cavity Design (original) (raw)

Design OF RF Cavities and RF Section Of S Band Klystron

High power CW Klystrons are widely used for advanced scientific applications such as high energy charged particle accelerator and plasma heating for nuclear fusion experiment. The present project has been taken up to study the design of RF section of 6MW, CW, S-Band Klystron tube which has a projected national requirement for high energy RF linear accelerators. The thesis presents the design methodologies adopted and results of the study during the course of project. At first approximate dimensions of re-entrant cavities with desired RF parameters to be used in RF section were determined using a 2D SUPERFISH code. This was followed by validation of design parameters using 3D CST- Microwave Studio code. Further, presuming approximately a gain of 10 dB per cavity, it was decided to use five cavities including input and output cavities. The design parameters of complete RF section including resonating frequency, gap length and R/Q of each individual cavity, centre to centre distance between consecutive cavities etc. were then determined using 1D Klystron design code AJDISK. This gives a fairly good estimate of various electrical and dimensional parameters of RF section to get desired tube performance

Simulation, Measurement and Tuning of a Prototype Disk Loaded RF Cavity

2017

Constant impedance accelerator RF cavities are constructed from similar resonator cells that stacked to each other. Best operation condition is achieved when all of cells resonate in one resonance frequency with similar quality factors. So, measurement and tuning of RF cavities is the critical step for final best operation of linear accelerators. In this paper, the electromagnetic computer simulations, RF measurement and final tuning of a nine cell periodic accelerator structure was represented. All of cavities tuned in one resonant frequency and according to theoretical concepts we obtain nine resonant modes from RF measurements by vector network analyzer. INTRODUCTION Linear electron accelerators are designed in various types and have wide applications in medicine, industry, agriculture and physics researches [1-2]. Main components of RF electron Linacs are RF power generators, power transmission waveguides, vacuum pumps and components, electron gun and acceleration cavities [3-4]...

Computation of Oscillation Frequency in a Plasma Filled Rectangular Cavity Resonator

Progress In Electromagnetics Research M, 2021

Oscillation frequency in a plasma filled rectangular dielectric resonator antenna is computed. Perturbation method for solving differential equation is applied to find oscillation frequencies of dielectric cavity resonator. Equilibrium distribution function of collisionless Boltzmann equation is slightly perturbed. Distribution function of plasma is perturbed by altering external applied electromagnetic field. Perturbed Boltzmann equation satisfies with the relaxation time approximation used for the collision. The resulting Maxwell equations are subjected to appropriate boundary condition. Multilinear algebra tensor decomposition technique is done to find eigenfrequincies of cavity resonator antenna considered in this paper. A simulation study of a ionized gas plasma antenna is done on HFSS. Numerically calculated oscillation frequency is cross verified with HFSS result and found in good agreement.

Design and measurements of microwave cavity and coupler for a klystron test stand

2019

DESIGN AND MEASUREMENTS OF A MICROWAVE CAVITY AND COUPLER FOR A KLYSTRON TEST STAND In recent years, usage of high power in modern technologies operating at microwave frequency range has been varying in research topics such as radar, plasma science, satellite communications and particle physics. Therefore, transmission of high power from a power generator to a specific target without loss is a key point of these research fields. In accordance with this purpose, a project has been started at the Kandilli Detector, Accelerator and Instrumentation (KAHVE) Laboratory of Boğaziçi University in Turkey which name is Design, Simulation and Production of an RF Circulator and Transmission Line. The aim of the project is to build a high power RF transmission line and circulator ope-rating at 800 MHz frequency. In order to perform this whole system after their installing, a simple pillbox cavity has been designed, simulated and fabricated. A cavity is not enough itself to test the system becaus...

COMSOL Simulation Study of Microwave Plasma in Cavity Resonator as a Transmitter-receiver Switch

Microwave discharge characteristics and variable plasma conductivity play an important role in design of microwave filters and the efficiency of radars and electronic warfare devices. A three dimension model was designed to study the effect of plasma formation on high power microwave (HPM) transmittance in cavity resonator based on COMSOL platform. The effect of gap length, electrode shape and size, coaxial port dimensions and gas pressure, on the electric field in the gap and insertion loss in cavity were investigated. The effect of the cross-section of ​​ coaxial port on the electric field created in the gap was investigated and the best values ​​were calculated and determined. The electron density profile, electron temperature, electric conductivity, elastic and inelastic collision frequency were calculated. The performance of plasma limiter was optimized. Results were compared with the experimental data.

Investigation of the resonance frequency and performance of a partially plasma filled reconfigurable cylindrical TE111 mode cavity

Physics of Plasmas, 2017

A partially plasma filled reconfigurable cylindrical cavity is proposed. Plasma offers an encouraging alternative to metal for a wide variety of microwave engineering applications. Implementation of a low-cost plasma element permits the resonant frequency to be changed electrically. The level of the resonant frequency shifts toward the empty-cavity resonant frequency and depends on certain parameters, such as the plasma diameter, relative permittivity and thickness of the plasma tube. In this article, we first introduce the partially plasma filled reconfigurable cylindrical cavity; then, the resonant frequency equation of the cavity is obtained by variational methods. Finally, we plot the resonant frequency versus different parameters of the cavity, which we compare with the results of the CST software. We show that the two results are compatible with each other.

Concept EM Design of the 650 MHz Cavities for the Project X

2011

Concept of the 650 MHz cavities for the Project X is presented. Choice of the basic parameters, i.e., number of cells, geometrical , apertures, coupling coefficients, etc., is discussed. The cavity optimization criteria are formulated. Results of the RF design are presented for the cavities of both the low-energy and high-energy sections.

Design, simulation and test of cavity in UHF band

Electronics Letters, 2009

A simple and successful design for a UHF cavity is presented with a rejection factor inferior to 247 dB for a difference of 1.6 MHz between the transmit frequency and the receive frequency, the insertion loss being less than 1 dB. A coil connected to the resonator ensures a 50 V adaptation. Modelling of the device, based on Pspice software, is described.