Gyrodevice oscillators and amplifiers (or gyro-oscillators gyro-amplifiers) are being utilized in a variety of applications where high power levels required at millimeter-wave frequencies. Gyro-oscillators, developed primarily for magnetic fusion research applications, have achieved near 1 MW pulse durations excess s frequencies above 100 GHz. Continued work on these devices should enable them to achieve continuous-wave operation multimegawatt the 100-GHz 200-GHz range, thereby meeting...

A method for computing the resonant frequency in a complex cavity consisting of series waveguide sections is derived. The analysis restricted to transitions which one wholly contained other. An eigenvalue problem formed by cascading scattering matrix from given section outwards ends cavity, with appropriate boundary conditions at ends. equation solved numerically searching frequency, Q being determined half ratio real imaginary part frequency. technique easily implemented and shows good...

The feasibility of future electron-positron colliders operating at energies >1 TeV will depend on both efficiency and cost the microwave amplifiers that can be developed to drive collider. To zeroth order, required number depends inversely parameter A=P/sub p/T/sub p///spl lambda//sup 2/, where /spl lambda/ is wavelength, P/sub p/ T/sub are, respectively, power duration amplifier output pulses. Thus, one goal research maximize A while keeping other values within bounds so as not excessively...

A set of tradeoff equations was simplified to obtain scaling laws for magnetron injection guns (MIGs). The constraints are chosen examine the maximum-peak-power capabilities MIGs. compared with exact solutions design and supported by MIG simulations in which each is designed double beam power an existing adjusting one four fundamental parameters.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Microwave tubes required to drive future 1-TeV linear colliders have challenging requirements, including 300-MW peak power at wavelengths near 3 cm. It is believed that gyrotrons good potential for development into the high power, gain, efficient amplifier this application. Presented here detailed design a 3-cm gyroklystron level of ~ 30 MW. This approximately three orders magnitude above state art, and 30-MW experimental study will be crucial step toward achieving goal. Novel problems...

The production of high-power microwave radiation from a large-orbit gyrotron in azimuthally periodic boundary systems is studied theoretically and experimentally. Linear growth rates are calculated for the 2π modes magnetron-like vane resonator (VR) hole- and-slot (HASR) using general growth-rate formalism. experiment involves interaction 2.3-MeV, 1-2-kA, 5-ns rotating electron layer with two different structures. About 500 MW produced Ku band 20-slot VR system about 300 X 10-slot HASR...

The design of a gyroklystron experiment capable fulfilling the expected requirements future electron-positron colliders is presented. an extension previous work that utilized interaction 500 kV beam and TE/sub 01//TE/sub 02/ circular cavities. Details electron gun which producing 800 A, 1 /spl mu/s are given. Modifications to existing code enhance system modeling described before circuit simulation results summarized.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML"...

The development of a 10-kW average power, 94-GHz gyroklystron amplifier is described. This power was obtained with 11% radio frequency (RF) duty factor and 92-kW peak in the TE/sub 01/ circular cavity mode. instantaneous bandwidth 420 MHz, efficiency 33.5%. Low-duty-factor testing also yielded as much 115 kW 600-MHz bandwidth. effort carried out over past three years represents record performance an at this frequency.

Experimental studies of amplification in a two-cavity X-band gyroklystron are reported. The system utilizes thermionic magnetron injection gun at voltages up to 440 kV and currents 190 A 1-\ensuremath{\mu}s pulses. Optimum performance is achieved by tapering the magnetic-field profile. Peak powers 20 MW ${\mathrm{TE}}_{01}$ mode 9.87 GHz measured with calibrated crystals methanol calorimetry. Resultant efficiencies excess 31% large-signal gains surpass 26 dB. experimental results good...

The operating characteristics of a two-cavity X-band gyroklystron experiment are reported. Beam voltages and currents up to 440 kV 200 A, respectively, generated in 1 mu s pulses by thermionic magnetron injection gun. Velocity ratios ( nu /sub perpendicular // z/) near one the output cavity used achieve peak powers 24 MW 9.87 GHz. maximum saturated efficiency more than 33% occurs at beam voltage 425 current 150 A. A large signal gain excess 34 dB is realized input just below start...

The theoretical performance of two nonlinear circular waveguide tapers constructed for a 10-GHz, 30-MW amplifier utilizing the lowest electric mode is evaluated. Mode coupling estimated with code that solves generalized telegraphist's equations numerically and compared results cascaded scattering matrix code. It found assuming sufficiently lossy conducting boundary allows evaluation modes pass through cutoff consideration backward usually in small changes forward reconcile numerical...

Conduction currents in polythene have been measured at stresses of from 05 to 15 MV cm-1 and several temperatures the range 45-85°C. The current increased exponentially with stress its temperature variation was consistent an activation process. Differences densities energies were observed aluminium carbon electrodes. possibility thermal breakdown above 50°C, where `intrinsic' electric strength varies time until breakdown, is examined using Vermeer's method results show clearly that cannot be...

An analytic and numerical study of the feasibility depressed collectors for gyrotrons accelerator applications is discussed, a specific design 10-GHz 30-MW gyroklystron realized. The conclusion that are feasible interest (i.e. P<or=100 MW, 10 GHz<f<35 GHz) their use would reduce capital costs RF system typical large by roughly 40%. In addition, scaling studies indicate fusion-related gyrotron oscillators, such as 1-MW, 280-GHz devices being developed on Compact Ignition Tokamak (CIT).<<ETX>>

Amplification studies of a two-cavity second-harmonic gyroklystron are reported. A magnetron injection gun produces 440 kV, 200--245 A, 1 \ensuremath{\mu}s beam with an average perpendicular-to-parallel velocity ratio slightly less than 1. The ${\mathrm{TE}}_{011}$ input cavity is driven near 9.88 GHz and the ${\mathrm{TE}}_{021}$ output resonates 19.76 GHz. Peak powers exceeding 21 MW achieved efficiency 21% large signal gain above 25 dB. This performance represents current state art for...

Abstract The operating characteristics of high power relativistic magnetron injection guns (MIGs) are studied theoretically. A set analytic expressions based on adiabatic approximations for a coaxial diode is used to identify feasible design regions in parameter space. Particle simulations then optimize particular designs. Results µs, 100 MW, 500 kV MIG, designed an X-band gyroklystron, critically examined.

Results are presented of investigations into the thermal ageing behavior cellulose paper insulation in which tests have been carried out between 100C and 160C on well-dried samples contained sealed glass vessels an atmosphere initially dry nitrogen gas. The degree has assessed by measuring time rate decrease several physical physico-chemical characteristics paper, e.g. burst strength, polymerization etc., conclusions were drawn concerning their relative sensitivities to state test sample. In...

Using methods described in a companion paper by Seaton, the partial wave integrals are calculated for transitions involving states 1s, 2s and 2p.

Experimental results for a 10 GHz TE/sub 01/ mode three-cavity gyroklystron with tunable penultimate cavity are presented. The electron beam was produced by pulse line modulator and magnetron injection gun which operates to 433 kV 225 A 1 mu s flat-top. Three-cavity circuits have peak power of 27 MW efficiency 32% energy 39 J. maximum gain 50 dB achieved at 20 MW, 37% 16 MW.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

In this paper, we report the design methodology and numerical results for two mode converters that are suitable high-power microwave applications. Both designed to operate at 11.424 GHz utilize periodic serpentine structures convert between modes with different azimuthal-mode indexes. The first converts about 98.5% of an incident linearly polarized TE/sub 12/ 01/ when oriented as H-plane bend, but has just 1% conversion all E-plane bend. second device a 11/ TM/sub over 99.99% effectiveness....

Abstract The project developed, implemented, and evaluated a complete asynchronous online version of an electric circuits laboratory for the 2020 summer fall semesters. In order to perform labs, electronics kits, which contained Diligent Analog Discovery 2 Device (AD2), or equivalent, as well breadboard, wires, operational amplifiers, diodes, resistors, capacitors, inductors, were sent each student. Videos made demonstrate set-up AD2 software hardware, operation assembly testing initial...

The experimental demonstration of a high average power W-band (75–110 GHz) gyroklystron amplifier is reported. has produced 118 AW peak output and 29.5% electronic efficiency in the TE011 mode using 66.7 kV, 6 A electron beam at 0.2% rf duty factor. At this operating point, instantaneous full width half-maximum (FWHM) bandwidth 600 MHz. 11% factor, up to 10.1 kW 33% with 66 4.15 beam. This represents world record performance for an frequency. FWHM 420 higher magnetic fields lower voltages,...

Experimental studies of high-power amplification in a novel three-cavity X-band gyroklystron are reported. The electron gun produces 520 A beam 470 keV electrons. voltage flat top is nearly $2\ensuremath{\mu}\mathrm{s}$ and the beam's average velocity ratio about 1. All cavities designed to operate ${\mathrm{TE}}_{011}$ coaxial mode near 8.6 GHz. Peak powers 75--85 MW measured. resultant efficiency $32%$ gain 30 dB. This performance good agreement with simulations represents threefold...

We report the operating characteristics of a sequence two-cavity second harmonic gyroklystrons which are derived in part from previous fundamental tube and utilize output cavities resonate at twice drive frequency. present results design simulations as well details stable range parameters. While is somewhat more susceptible to spurious oscillations sensitive parameter variations than device, there still considerable space available for amplifier operation. Peak powers above 30 MW obtained...

The scattering matrix formulation for complex right-circular activities is extended to coaxial circuits with variable inner radii. modified eigenvectors, which include the TEM wave, and boundary conditions are presented. properties of several configurations examined transmission measurements shown be in good agreement theory.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Experimental and theoretical studies conducted at the University of Maryland on production high-power microwave radiation in cusp-injected, large-orbit devices are reviewed. Three classes belonging to this category discussed. In first case, an axis-encircling rotating electron beam interacts via negative mass instability with modes a smooth cylindrical waveguide, producing broadband multiple harmonics cyclotron frequency. second multiresonator magnetron circuit designed provide mode control,...