Foundations for microwave engineering, 2nd edition wiley. But, these devices are replaced by semiconductor microwave devices. Reflex klystron working, oscillator and applegate diagram. Reflex klystron consists of an electron gun, a cathode filament, an anode cavity, and an electrode at the cathode potential. Difference between two cavity klystron and reflex klystron. Cavity of a repeller klystron another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron repeller klystron. A loop coupling is used inside the cavity to get the output. An ability to identify, formulate and analyze engineering problems using knowledge of basic mathematics and engineering sciences. Foundations for microwave engineering, second edition, covers the major topics of microwave engineering. 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. Velocity modulation, power output and frequency versus reflector voltage electronic admittance. Revathi klystron power supply reflex klystron isolator frequency meter detector mount c.
The mathematical analysis of this chapter is illustrative rather than exact. 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. Simulating a new low q 6cell xband klystron output cavity. Scribd is the worlds largest social reading and publishing site. 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.
Alberto leggieri1, davide passi 1, franco di paolo, giovanni saggio1. The conventional vacuum tubes, such as triodes, tetrodes, and pentodes, are still used as signal sources of low output. The multiphysics design of a ghz klystron buncher cavity is described in this paper. 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. An essential reference book for the practicing microwave engineer, it features. The reflex klystron contains a reflector plate, referred to as the. All these components are enclosed in a glass envelope. A tool for the simulation of high frequency reflex klystrons is presented.
To study the characteristics of the reflex klystron tube and to determine its electronic tuning range. Microwave tubes high frequency limitations principle of operation of multicavity klystron, reflex klystron, traveling wave tube, magnetron. Klystron tube 2k25 the klystron tube 2k25 is a single cavity variable frequency microwave generator of low power and low efficiency. With the help of applegate diagram illustrate the phenomenon of bunching. A klystron is a specialized linearbeam vacuum tube evacuated electron tube the name klystron comes from the stem form. Anatoly krasnykh, slac, box 4349 stanford, ca 94309. In this klystron, a single pair of grids does the functions of both the buncher and the catcher grids. Planar transmission lines, as well as an appendix that.
Characteristics of a reflectiontype microwave modulator. The difference between reflex and twomulti cavity klystron is that, reflex klystron uses single cavity for modulationdemodulation. Comsol conference 2015 grenoble multiphysics design of a klystron buncher the preliminary em analysis is the first step. Another tube based on velocity modulation, and used to generate microwave energy, is the reflex klystron figure 29. This microwave generator, is a klystron that works on reflections and oscillations in a single cavity, which has a variable frequency. In this video, i have explained two cavity klystron amplifier with following points 1. Here, the evolution of the system in a complete klystron is shown and some considerations are discussed on the feasibility of over 100 ghz. May 01, 2014 reflex klystron free download as powerpoint presentation. Critical quantities are exposed to multiple physics effects acting on narrow dimensions modified by power dissipations. The ranges of all these voltages are given in the specification data sheet. 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. A cloud of thermionic electrons is generated by heating a filament inside a vacuum tube. 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. A singlecavity klystron in which the electron beam is reflected back through the cavity resonator by a repelling electrode having a negative voltage. Knowing the maximum voltage of two adjacent modes, mode number can be computed using the relation prepared by m. 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. As shown in the given diagram it is composed of heater, cathode, focusing electrodes and repeller anode. Request pdf barkhausen model of reflex klystron oscillator reflex klystron is an. After the focusing electrodes there is a cavity resonator which encircles the glass envelope. 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. Four long questions of 10 marks each to be answered taking one from unit i and 3 from unit ii.
The proposed device uses a micro machined input section described in last comsol conference appointment in 2015 in grenoble 3. Our years of experience have made us one of the leaders in the manufacturing of these magnets. How are oscillations produced in a reflex klystron. It is a low power tube with a single and work as an oscillator. An ability to provide solution and to design electronics. Explain and perform the reflex klystron characteristics using microwave bench setup. Linear accelerator linac as well as the klystron magnets, alpha magnetics also.
The multiphysics analysis of a ghz klystron is described in this paper. Investigation of frequency modulation of a reflex klystron 49 c. Experiment4 study of the characteristics of the klystron tube. Derive expressions for bunched beam current and efficiency. Engineering education and particularly majors in microwave electronics have gone. It has two microwave cavity resonators the catcher and the buncher. 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. Work supported by department of energy contract deac0376sf00515 abstract major changes to the next linear collider nlc design. A comprehensive analysis of reflex klystrons is developed by considering the electrons as particles acted upon by forces which modify their motion. 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. Electrons are not intercepted by the cavity anode grid. 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. It is reliable power source with very high regulation and low ripple contents.
We have developed algorithms for designing diskloaded travelingwave output structures for xband klystrons to be used in the slac nlc. Microwave engineering 1 books for ec branch students of b. Various fundamental principle are used for the analysis and design purpose with the application of field measurement techniques. Reflex klystron oscillator pdf source of an electronbeam and the radiofrequency por tion of the klystron is independent of the electron source. 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. The klystron beam focusing system is one of the key components in the whole system.
It is given the name reflex klystron because of its reflex action of electron beam. A reflex klystron is operated at 5ghz with dc beam voltage v, beam current 20ma, repeller space lcm for 1. Important question and answers on reflex klystron with. Reflex klystron article about reflex klystron by the free. Travelling wave tube is a cylindrical structure which contains an electron gun from a cathode tube. To measure the directivity and coupling of a directional coupler. Performance evaluation of klystron beam focusingsystem with. This is similar to that done in the case of klystron earlier. Also draw the schematic of reflex klystron and explain its working.
Have strong foundation in mathematical, scientific, engineering fundamentals and communication skills necessary to formulate, understand, analyze and solve. Observation, analysis and calculation of typical parameters and their effect simulate microwave mathematical concepts in an innovative way. Cavity grids and repeller are plane and parallel, and also very large in extent. Ph0101 unit 2 lecture 6 2 reflex klystrons the reflex klystron has been the most used. From each mode and the band of frequencies over which the circuit can be tuned. A reflex klystron also can be treated as a delayed feedback oscillator, where the delay is caused by. The electrons are fired into one end of the tube by an electron gun. 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. Which is impossible and not feasible to use other components for this purpose. 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. Reflex klystron is also known as a sutton klystron.
Parametric analysis of micromachined reflex klystrons for operation. Oscillating klystron how is oscillating klystron abbreviated. Microwave and radar engineering with lab manual by vinith chauhan m. Microwave engineering reflex klystron tutorialspoint. Its presentation defines the accepted standard for both advanced undergraduate and graduate level courses on microwave engineering. The klystron power supply skps610 has built in modulation facilities of amplitude and. Sep 27, 2017 in this video, i have explained reflex klystron with following points 1. Klystron multi cavity klystron, reflex klystron, working. Based on the monte carlo technique, this simulation includes loss.
It is known by this name due to its reflex action of electron beam. 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. 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 reflex klystron amplifier is used as an oscillator in a modulator in microwave transmitters and radar receivers. The reflex klystron is also called as sutton tube invented by robert sutton. 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. Microwave spectrum and bands, applications of microwaves. 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.
Give the difference between two cavity klystron and reflex klystron. Reflex klystron free download as powerpoint presentation. To measure the klystron frequency by slotted section method 4. Rf input is sent to one end of the helix and the output is drawn from the other end of the helix. 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. A reflex klystron is an obsolete type in which the electron beam was reflected back. To plot radiation pattern of a horn antenna in horizontal and vertical planes. 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. Reflex klystron telecommunications engineering mechanics. 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. Draw the neat figure of reflex klystron and its applegate diagram. The relatively low efficiency of the reflex klystron is not important for many applications, as for. A reflex klystron achieves the same bunching by causing the beam to reverse. Klystron power supply, klystron tube, isolator, frequency meter, variable attenuator, detector mount, waveguide stand, vswr meter and bnc cable.
Together, the magnetron and the klystron made possible airborne sband radar, a major factor in securing air. The main difference between two cavity reflex klystron amplifier. This type of klystron is mostly used for the purpose of amplification of microwave length of frequencies. 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. Timedomain picmodeling of the multiple cavity klystron oscillator with delayed feedback. An electron gun focusses an electron beam with the velocity of light. In the reflex klystron the electron beam passes through a single resonant cavity. Measurement of power, wavelength, impedance, swr, attenuation, q and phase shift. Together, the magnetron and the klystron made possible airborne sband radar, a major factor in securing air superiority for the raf. To measure electronics and mechanical tuning range of a reflex klystron 2. After passing through the resonant cavity they are reflected by a negatively charged reflector electrode for another. The reflex klystron contains a reflector plate, referred to as the repeller, instead of the output cavity used in other types of klystrons. Timedomain particleincell modeling of delayed feedback klystron oscillators article pdf available in ieee transactions on electron devices 616.
Lowpower klystrons are used as oscillators in terrestrial microwave relay. The brothers russell and sigurd varian of stanford university are the. The schematic diagram of a reflex klystron tube is shown in fig. May 31, 2014 knowing the maximum voltage of two adjacent modes, mode number can be computed using the relation prepared by m.
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