Brown s work to adapt magnetron principles to create a new broadband amplifier is generally recognized as the first cfa, which he called an. This equipment allows the intrapulse characteristics of the crossed field amplifiers to be measured individually for phase stability, fidelity, and amplification. A multistage cascade cross field amplifier cfa rf chain is employed, each. The analysis of the injected reentrant beam crossed field amplifier is not complete.
Recent advances in non reentrant crossedfield forwardwave. Noise figure calculation and measurement for lowpower. Klystrons, traveling wave tubes, magnetrons, crossfield. The design of an sband axial injection crossed field amplifier capable of 5 kw cw and x db of gain is described. Crossedfield amplifier internal operation the electric and magnetic fields in a cfa are perpendicular to each other crossed fields. Browns work to adapt magnetron principles to create a new broadband amplifier is generally recognized as the first cfa, which he called an amplitron. Description of the function of a crossedfield amplifier tube cfa or amplitron. Different types of microwave tubes amplifier wireless.
Feasl bl llty model advanced crossedfield ampll fler for. Simulation and modeling of selfmodulated reentrant beam crossed field amplifier. We cannot guarantee that crossed field microwave devices v2 book is in the library. Errors in the assembly of the crossed field electron gun were corrected, and dimensions of the gun were checked against the design. Present testing methods are lacking in the coverage of power for freque. Recent work on the linear form of the injectedbeam forwardwave crossed field amplifier has greatly reduced the problem and promises to put this device into the high gain class along with klystrons and travelingwave tubes. This is the same type of field interaction used in a magnetron. Although the physical appearance differs from that of linearbeam tubes, which are usually circular in format, the major difference is in the interaction physics that requires a magnetic field at right angles to the applied electric field. As part of the project, a design procedure for crossed field guns is being developed. Noise on the beam will be the chief limiting factor in the gain attainable in crossed field amplifiers. The field effect transistor fet is a transistor that uses an electric field to control the shape. Studies of a second design of the amplifier, using wave lengths, show higher gain and greater computational stability with less stream feedback.
Jul 23, 2020 a crossedfield amplifier cfa is a specialized vacuum tube, first introduced in the mid1950s and frequently used as a microwave amplifier in veryhighpower transmitters. Early background experience for the choice of this tube type was established by low power experiments. Ec67 01 rfmw syllabus notes download link is provided and students can download the ec 6701 syllabus and lecture notes and can make use of it. Download and read free online klystrons, traveling wave tubes, magnetrons, crossfield. Several varieties exist including the forwardwave backwardwave types, and the injectedbeam continuouscathode emittingsole. Ec6701 notes syllabus all 5 units notes are uploaded here. Klystrons, traveling wave tubes, magnetrons, crossfield amplifiers, and gyrotrons artech house microwave library kindle edition by a. Review of the highpower vacuum tube microwave sources. Create free account to access unlimited books, fast download and ads free. Backward wave crossed field amplifier and oscillator. L3harris is the world leader in crossed field amplifier cfa production and development, delivering devices from l to xband with power levels from 60 kw to 5 mw peak. A solid state radar transmitter pulse modulator system capable of generating high power operating pulses having pulse width and pulse repetition rate agility and being programmable for output pulse current over a substantial range of peak current values to produce corresponding values of transmitter output power. It is a linear tube in which the magnetic field is applied to focus the electron and electric field is applied to drift the electron.
The crossed field amplifier amplitron the crossed field amplifier cfa, commonly known as an amplitron and sometimes referred to as a platinotron, is a broadband microwave amplifier that can also be used as an oscillator. Because the beam is reentrant, the crossed field amplifier will oscillate if the circuit gain becomes high. The continuouscathode emittingsole crossedfield amplifier. We present the results of a theoretical study of the microelectronic modification of a crossed field amplifier with two. Quarterly progress report study of crossed field amplifiers april 15, 1965 da 36039 amc02164e shield edgun crossed field amplifier prof. Media in category crossedfield amplifier the following 4 files are in this category, out of 4 total. Federal contract opportunity for cross field amplifier cfa electron tubes n0010420rd006. The amplifier chosen as being best suited to meet all of the objectives of the program was the axial injection crossed field amplifier. Feb 03, 1997 secondaryelectronemission processes under electron bombardment play an important role in the performance of a variety of electron devices. Klystrons, traveling wave tubes, magnetrons, crossfield amplifiers, and gyrotrons artech.
Early indications are that the efficiency of this design is greater. Reentrant emittingsole crossed field amplifier tube. In the spy 1 a transmitter configuration, a single. Output tubes, klystrons, travelingwave tubes, magnetrons, crossedfield amplifiers, and gyrotrons. The 48 kw klystron and the 5 kw crossed field directional amplifier cfda were considered to be the leading tube contenders, with the amplitron version of the cfa having the highest potential performance, lowest weight, 1 ongest 1 i fe and 1 owest cost. The cfa is similar in operation to the magnetron and is capable of providing relatively large amounts of power with high efficiency. This configuration, which was selected to gener ate the required power levels while having inherently high system reliability under casualty conditions, was chosen after comparisons with alternative designs having fewer tubes.
Gyratron crossed field tube which can be used as an amplifier or an oscillator. Anna university regulation 2017 syllabus pdf for all departments i viii semester download. Crossed field amplifier the crossed field amplifier cfa is constructed very similar to a magnetron. Skowron invited paper absfractthe crossed field amplifier cfa is an outgrowth of the magnetron. Experimental cathodedriven circuitonemittingsole crossed field amplifiers have been designed and built at sband under a navy program contract no. Crossedfield amplifiers, crossedfield amplifiers cfas. Low noise crossed field amplifier download pdf info publication number us4814720a. Ieee transactions on electron devices, vol 39, no 6, june 1992 zyxwvutsrq 1529 guiding center fluid model of the crossed field amplifier spilios a. This specific format of crossed field amplifier cfa was developed by sfd laboratories. Cfa has a noisier output than either a klystron amplifier or twt. Annamacharya institute of technology and sciences tirupati aitsece mwe page 2 tuning of conventional magnetrons is accomplished by moving capacitive tuners or by inserting symmetrical arrays of plungers into the inductive portions of the device. Mar 16, 2017 crossed field amplifiers have very good efficienciesup to 80%, but the gain is limited. Drobot abstracta closed, nonlinear set of fluid equations, based on zyxw space, or following a window in synchronism with the the electron guiding center orbits, is developed to model the phase.
Pdf crossed field microwave devices v2 download full. A crossedfield amplifier cfa is a specialized vacuum tube, first introduced in the mid1950s and frequently used as a microwave amplifier in veryhighpower transmitters raytheon engineer william c. The crossed field amplifier cfa, is a broadband microwave amplifier that can also be used as an oscillator stabilotron. Us4827267a high availability solid state modulator for. The major difference is that the cfa requires an rf input in addition to the electrical input and the magnetic field. It is a specialized vacuum tube, first introduced in the mid1950s and frequently used as a microwave amplifier in veryhighpower transmitters. It does this by taking energy from a power supply and controlling the output to match the input signal shape but with.
To read and print pdf files, download adobe acrobat reader. This paper contains more of our measurements and also some theoretical work in which we have investigated the effect of changing the drift space. Noise on the beam will be the chief limiting factor in the gain attainable in crossed field. Typically, the first stage and the second stage are travelingwave tubes twt and the final stage is a crossed field amplifier. Apr 30, 2016 pdf download power frequency magnetic fields and public health pdf full ebook. Download it once and read it on your kindle device, pc, phones or tablets. Pdf a high power crossfield amplifier at xband researchgate.
The outputs of a relatively few fixed oscillators can be mixed in various combinations to produce a wide range of frequencies. Ec6701 rf and microwave engineering syllabus notes question. At the time, the recently developed linear beam travelingwave tube twt suffered from the shortcoming of low efficiencv. Physics 862 accelerator system introduction to rf and microwave. The first practical electronic device which could amplify was the. Crossedfield amplifier wikimili, the best wikipedia reader. It was the purpose of the first years work to investigate the electrical design and the technology of fabricating delay line circuits suitable for use in such an amplifier. The purpose of the program is the development of a crossed field ampli fier in the 7 to 11 go range capable of 2 kilowatts cw output. Power amplifier transmitter using crossed field amplifiers. Recent advances in non reentrant crossedfield forward.
L3harris cfas are currently being produced for some of the worlds most advanced radar systems such as the aegis anspy1 and the patriot missile system. If you find our videos helpful you can support us by buying something from amazon. Bill i on bit random access cryoe lectric memory radctd r64376 n6515249. The cw design is experimentally verified in a low duty demountable amplifier. Amplitron crossed field amplifier other names in the literature.
H6 systems proposes building a transmitter based on a modified coupled cavity twt from cpi to increase coverage of milstd464c. Get your kindle here, or download a free kindle reading app. Download fulltext pdf download fulltext pdf download fulltext pdf. Gain was nominally 30 db at efficiencies as high as 807. Cross field amplifier cfa electron tubes n0010420rd006. The amplifiers in this type of power amplifier transmitter must be broadband microwave amplifiers that amplify the input signals without frequency distortion. Pdf simulation and modeling of selfmodulated reentrant. The action of electronics taking energy away from the ac fields is an undesirable effect. Pdf guiding center fluid model of the crossedfield. An amplifier, electronic amplifier or informally amp is an electronic device that increases the power of a signal. The rf dynamic range of the cfa is enhanced by proper design of a reflector electrode at the sides of the interaction space. Pdf a high power crossfield amplifier cfa is under development at slac to provide sufficient peak power to feed a section of an xband accelerator. The power output of the crossed field amplifier is essentially independent of the radiofrequency drive signal, and the device thus operates as a saturated amplifier.
A computer simulation of the aegis signal processor was then used to predict the radar system performance. Cross field devices the magnetron is the pioneering device of the family of crossed field tubes. The particular device we have evaluated in detail is the amplitron, manufactured. The slow wave structure of the cathode is accurately proportioned and spaced to have a dispersion curve near to the dispersion of the slow wave structure of the anode to permit cross coupling of the rf input from the slow wave structure of the anode to the slow wave. An amplifier is effectively the opposite of an attenuator. Cfa cross field amplifiers linked to trusted tde listed vendors. A guiding center fluid model involving a single rf mode of slowly varying amplitude and phase is used to study the longtime behavior of a distributed emission, reentrant crossed field amplifier. O 63492t crossed field ampl ifier xband crossed field amplifier capable of. Click get books and find your favorite books in the online library.
The configuration of a typical presentday distributed emission amplifier is similar to that of the magnetron except that the device has an input for the introduction of rf energy into the circuit. In a forward wave low noise cross field amplifier a slow wave structure is disposed about a predetermined portion of the cathode. While in some devices, the anode and the grid require materials that suppress the secondaryelectrongeneration process, the crossed field amplifier cfa is an example where the cathode requires an efficient secondaryelectronemission material. Rao the aim of this project is to design and test a shieldedgun, crossed field amplifier. Ec6701 rf and microwave engineering syllabus notes. In magnetron the magnetic field and electric field are perpendicular to each other hence it is called as cross field device.
This characteristic makes it unsuitable for amplifying amplitudemodulated signals. The dc field extends radially between adjacent anode segments by the rf oscillations induced in the cavity tank circuits of the anode block. The measurements we have made lead us to believe that the crossed field amplifier is not necessarily noisy and also have led us into considering possibilities of making ultralownoise amplifiers. Crossedfield amplifier simulations using a moving wavelength. Peak and average power levels achieved were approximately one uegawatt and 20 kilowatts, respectively. A typical frequency synthesizer consists of a bank of oscillators producing different fixed frequencies. In mti systems the selected oscillator frequencies are mixed with a coherent. Crossed field arrwlifier the crossed field amplifier for our service may be considered as a descendant of the cavity magnetron.
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