Engineering education and particularly majors in microwave electronics have gone. The analysis is similar to earlier explanations of electron bunching in a fieldfree drift space and predicts a similar current distribution when bunching takes. The relatively low efficiency of the reflex klystron is not important for many applications, as for. Draw the neat figure of reflex klystron and its applegate diagram. We have developed algorithms for designing diskloaded travelingwave output structures for xband klystrons to be used in the slac nlc. Foundations for microwave engineering, second edition, covers the major topics of microwave engineering. In fact, according to kek injector operating statistics during 10 years in 2000s, the failures in focusing solenoids were the most frequent reasons to exchange klystron assemblies among the other. Cavity grids and repeller are plane and parallel, and also very large in extent. In recent years the apid progress in rf and microwave electronics has created an increasing demand for virtual training platform which can provide a. Simulating a new low q 6cell xband klystron output cavity. A singlecavity klystron in which the electron beam is reflected back through the cavity resonator by a repelling electrode having a negative voltage.
Alberto leggieri1, davide passi 1, franco di paolo, giovanni saggio1. Transit time effect velocity modulation current modulationbunchingtwo cavity klystron amplifier reflex klystron slowwave structures helix travelingwave tubes convection current axial electric field wave modes bandwidth, power and gain considerations cross field device magnetronpower and frequency considerations. Microwave spectrum and bands, applications of microwaves. Typical operational problems with a klystron input drive power is too low and klystron is not saturated although this is required if the tube is included in a feedback loop reduced output power, efficiency, and increased output power amplitude jitter wrong cathode filament current wrong perveance. It has two microwave cavity resonators the catcher and the buncher. Investigation of frequency modulation of a reflex klystron 49 c. Microwave tubes high frequency limitations principle of operation of multicavity klystron, reflex klystron, traveling wave tube, magnetron. An electron gun focusses an electron beam with the velocity of light.
To study the characteristics of the reflex klystron tube and to determine its electronic tuning range. Reflex klystron is also known as a sutton klystron. Klystron power supply, klystron tube, isolator, frequency meter, variable attenuator, detector mount, waveguide stand, vswr meter and bnc cable. The schematic diagram of a reflex klystron tube is shown in fig. The klystron beam focusing system is one of the key components in the whole system.
An essential reference book for the practicing microwave engineer, it features. Barkhausen model of reflex klystron oscillator request pdf. Sep 27, 2017 in this video, i have explained reflex klystron with following points 1. File type pdf microwave engineering lab venkataraghavan t mathematics of investment and credit solutions manual 5th edition pdf, jeep liberty manual transmission timing belt, carnegie course 3 answers, periodic table webquest answer key, 2001 gmc yukon xl owners manual download, 1995 cadillac deville wiring diagrams 49 l engine, question. Its presentation defines the accepted standard for both advanced undergraduate and graduate level courses on microwave engineering. Microwave engineering 1 books for ec branch students of b. The difference between reflex and twomulti cavity klystron is that, reflex klystron uses single cavity for modulationdemodulation. Electrons are not intercepted by the cavity anode grid. A reflex klystron achieves the same bunching by causing the beam to reverse. Oct 01, 2014 microwave linearbeam tubes 0 type 90 introduction we turn now to a quantitative and qualitative analysis of several conventional vac uum tubes and microwave tubes in common use. Derive expressions for bunched beam current and efficiency. Klystron tube 2k25 the klystron tube 2k25 is a single cavity variable frequency microwave generator of low power and low efficiency. Anatoly krasnykh, slac, box 4349 stanford, ca 94309. Together, the magnetron and the klystron made possible airborne sband radar, a major factor in securing air superiority for the raf.
The mathematical analysis of this chapter is illustrative rather than exact. This is similar to that done in the case of klystron earlier. The electrons are fired into one end of the tube by an electron gun. After passing through the resonant cavity they are reflected by a negatively charged reflector electrode for another. It is given the name reflex klystron because of its reflex action of electron beam. Critical quantities are exposed to multiple physics effects acting on narrow dimensions modified by power dissipations. The conventional vacuum tubes, such as triodes, tetrodes, and pentodes, are still used as signal sources of low output.
In this video, i have explained two cavity klystron amplifier with following points 1. Work supported by department of energy contract deac0376sf00515 abstract major changes to the next linear collider nlc design. Performance evaluation of klystron beam focusingsystem with. It is reliable power source with very high regulation and low ripple contents. To measure the directivity and coupling of a directional coupler. After the focusing electrodes there is a cavity resonator which encircles the glass envelope. A cloud of thermionic electrons is generated by heating a filament inside a vacuum tube. Planar transmission lines, as well as an appendix that. Reflex klystron is a microwave device that works on principle of velocity modulation in addition to current modulation.
An ability to provide solution and to design electronics. Two cavity klystron amplifiers working, amplification. Design study on the high power klystron for komac hyeokjung kwon1, kangok lee1, hansung kim2, minjoon park2, moonsung chun2, kiehyung chung2, seungjeong noh3 1 korea accelerator and plasma research association, chonan 330825, korea. Klystron multi cavity klystron, reflex klystron, working. The multiphysics analysis of a ghz klystron is described in this paper. Oscillating klystron how is oscillating klystron abbreviated. Our years of experience have made us one of the leaders in the manufacturing of these magnets. All these components are enclosed in a glass envelope. Timedomain particleincell modeling of delayed feedback klystron oscillators article pdf available in ieee transactions on electron devices 616. The multiphysics design of a ghz klystron buncher cavity is described in this paper.
Cavity of a repeller klystron another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron repeller klystron. Microwave and radar engineering with lab manual by vinith chauhan m. Linear accelerator linac as well as the klystron magnets, alpha magnetics also. The reflex klystron also known as a sutton tube after one of its inventors, robert sutton was a low power klystron tube with a single cavity, which functioned as an oscillator. Have strong foundation in mathematical, scientific, engineering fundamentals and communication skills necessary to formulate, understand, analyze and solve. It was used as a local oscillator in some radar receivers and a modulator in microwave transmitters the 1950s and 1960s, but is now obsolete, replaced by semiconductor. A tool for the simulation of high frequency reflex klystrons is presented. Together, the magnetron and the klystron made possible airborne sband radar, a major factor in securing air. Scribd is the worlds largest social reading and publishing site.
Foundations for microwave engineering, 2nd edition wiley. To measure the klystron frequency by slotted section method 4. Here, the evolution of the system in a complete klystron is shown and some considerations are discussed on the feasibility of over 100 ghz. A quantitative mathematical analysis based upon oscillator theory is also derived and the results are presented in a series of universal curves which are used to. From each mode and the band of frequencies over which the circuit can be tuned. Also draw the schematic of reflex klystron and explain its working. Observation, analysis and calculation of typical parameters and their effect simulate microwave mathematical concepts in an innovative way. A reflex klystron is an obsolete type in which the electron beam was reflected back. Reflex klystron consists of an electron gun, a cathode filament, an anode cavity, and an electrode at the cathode potential. Reflex klystron working, oscillator and applegate diagram. Reflex klystron article about reflex klystron by the free. Velocity modulation, power output and frequency versus reflector voltage electronic admittance. Characteristics of a reflectiontype microwave modulator. The reflex klystron makes use of velocity modulation to transform a continuous electron beam into.
Knowing the maximum voltage of two adjacent modes, mode number can be computed using the relation prepared by m. Lowpower klystrons are used as oscillators in terrestrial microwave relay. In this klystron, a single pair of grids does the functions of both the buncher and the catcher grids. Measurement of power, wavelength, impedance, swr, attenuation, q and phase shift. The reflex klystron is also called as sutton tube invented by robert sutton. Reflex klystron free download as powerpoint presentation. But, these devices are replaced by semiconductor microwave devices. An ability to identify, formulate and analyze engineering problems using knowledge of basic mathematics and engineering sciences. With the help of applegate diagram illustrate the phenomenon of bunching.
This microwave generator, is a klystron that works on reflections and oscillations in a single cavity, which has a variable frequency. Request pdf barkhausen model of reflex klystron oscillator reflex klystron is an. The reflex klystron contains a reflector plate, referred to as the. According to the us department of education the percentage of bachelors degrees conferred in stem fields in the united states was lower in 20082009 24. Explain and perform the reflex klystron characteristics using microwave bench setup. Based on the monte carlo technique, this simulation includes loss. A comprehensive analysis of reflex klystrons is developed by considering the electrons as particles acted upon by forces which modify their motion. Various fundamental principle are used for the analysis and design purpose with the application of field measurement techniques. Another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron figure 29.
It has been employed to calculate the microwave power dissipations when wall current flows on the cavity walls while it receives the operative input signal 1 w. May 01, 2014 reflex klystron free download as powerpoint presentation. A loop coupling is used inside the cavity to get the output. To measure electronics and mechanical tuning range of a reflex klystron 2. A reflex klystron also can be treated as a delayed feedback oscillator, where the delay is caused by. The reflex klystron contains a reflector plate, referred to as the repeller, instead of the output cavity used in other types of klystrons. Which is impossible and not feasible to use other components for this purpose. The reflex version of the klystron, perfected at sperry and in british laboratories, served as the local oscillator in superheterodyne radar receivers. Klystron oscillator reflex klystron traveling wave tube biological effect of microwaves. It is known by this name due to its reflex action of electron beam. Microwave engineering reflex klystron tutorialspoint.
A klystron is a specialized linearbeam vacuum tube evacuated electron tube the name klystron comes from the stem form. Klystron solenoid magnets since the early 1960s, alpha magnetics has been manufacturing klystron solenoid magnets for use in communications, radar, microwave research and particle accelerators. As shown in the given diagram it is composed of heater, cathode, focusing electrodes and repeller anode. This type of klystron is mostly used for the purpose of amplification of microwave length of frequencies. The proposed device uses a micro machined input section described in last comsol conference appointment in 2015 in grenoble 3. Reflex klystron telecommunications engineering mechanics. A reflex klystron is operated at 5ghz with dc beam voltage v, beam current 20ma, repeller space lcm for 1. Timedomain picmodeling of the multiple cavity klystron oscillator with delayed feedback. A reflex klystron consists of an electron gun, a cavity with a pair of grids and a repeller plate as shown in the above diagram.
In this klystron, a single pair of grids does the functions of both the buncher and the catcher. Important question and answers on reflex klystron with. To plot radiation pattern of a horn antenna in horizontal and vertical planes. The model klystron power supply skps610 is general purpose laboratory power supply which is specially designed to use for reflex klystron tubes of s to x band frequency range. Travelling wave tube is a cylindrical structure which contains an electron gun from a cathode tube. Microwave tubes as microwave source oscillators and amplifiers.
Work supported by department of energy contract deac0376sf00515 abstract major changes to the next linear collider nlc design were facilitated by the experimental testing of the 75 mw xband klystron at a 3. May 31, 2014 knowing the maximum voltage of two adjacent modes, mode number can be computed using the relation prepared by m. Rf input is sent to one end of the helix and the output is drawn from the other end of the helix. Klystron oscillator reflex klystron traveling wave tube. Revathi klystron power supply reflex klystron isolator frequency meter detector mount c. The brothers russell and sigurd varian of stanford university are the.
Ph0101 unit 2 lecture 6 2 reflex klystrons the reflex klystron has been the most used. Reflex klystron oscillator pdf source of an electronbeam and the radiofrequency por tion of the klystron is independent of the electron source. It is a low power tube with a single and work as an oscillator. The analysis is similar to earlier explanations of electron bunching in a fieldfree drift space and predicts a similar current distribution when bunching takes place in a reflecting field.
The reflex klystron amplifier is used as an oscillator in a modulator in microwave transmitters and radar receivers. The ranges of all these voltages are given in the specification data sheet. Four long questions of 10 marks each to be answered taking one from unit i and 3 from unit ii. Rectangular waveguides tetm mode analysis, expressions for fields, characteristic equation and cutoff frequencies, filter characteristics, dominant and degenerate modes, sketches of te and tm mode fields in the crosssection, mode characteristics phase and group velocities, wavelengths and impedance. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. The main difference between two cavity reflex klystron amplifier. How are oscillations produced in a reflex klystron.
Experiment4 study of the characteristics of the klystron tube. Give the difference between two cavity klystron and reflex klystron. Rectangular waveguides tetm mode analysis, expressions for fields, characteristic equation and cutoff frequencies, filter characteristics, dominant and degenerate modes, sketches of te and tm mode fields in the crosssection, mode characteristics phase and group velocities, wavelengths and. Difference between two cavity klystron and reflex klystron. In the reflex klystron the electron beam passes through a single resonant cavity. The proposed device uses an integrated injectionbunching section described in last comsol conference appointment. Reflex klystron the analysis of a reflex klystron is similar to that of a twocavity klystron to some extent and is subjected to the following approximations. The klystron power supply skps610 has built in modulation facilities of amplitude and. Comsol conference 2015 grenoble multiphysics design of a klystron buncher the preliminary em analysis is the first step.
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