V. D. Yeryomka

Development of Ka-range magnetron for portable radar

An experimental prototype of a pulse magnetron has been developed, having the output power of 2.5 kW at a frequency of 35 GHz with the operation voltage of 6.5 kV. The interaction space of the magnetron has been extended due to the properly selected operation mode - it works at the first negative spatial harmonics. The magnetrons structural scheme includes the main secondary-emission cold cathode and an additional side thermoemission cathode. This design provides for a substantial prolongation of magnetrons service life, while the pulse duration and the duty factor increase.

Numerical and experimental investigation of a 35 GHz 20-vane spatial-harmonic magnetron

A 35 GHz 3 kW spatial-harmonic magnetron employing 20-vane resonator is numerically and experimentally investigated. Simulated output power is 3.2 kW at beam voltage of 6.5 kV and anode current of 4 A using 3D PIC simulation. The measured resonant frequency for operation mode of p = 16 is 34.96 GHz.

Terahertz range coaxial klinoorotron oscillator

The coaxial klinoorotron with inhomogeneous focusing magnetic field in which the klinotron effect is applied to improve the efficiency of energy exchange between the tubular electron beam and electromagnetic field of the open coaxial cavity is investigated. It is shown that in this device with double electron optics at f = 100 GHz and at V<inf>0</inf> =2,8 kV, B<inf>0max</inf> −0,4…0,436 T, B<inf>0min</inf> =0,266…0,338 T, I<inf>Q</inf> =3… 10 A of relatively thick double electron beams (Δr/r<inf>0</inf> = 0,01 ^ the efficiency 10… IS % is achieved.

Submillimetric-wave magnetron oscillator: Simulation of its specific features

The application of the drift-orbital theory and 3-D numerical simulation is shown to offer ample scope for constructing a small-sized pulse cold-cathode sub-millimetric-wave magnetron oscillator. As the analytical estimation and computer-aided experiments indicate, the output power of this type of magnetron varies between hundreds of milliWatts and hundreds Watts.

Efficiency of coaxial klinoorotron

The coaxial klinoorotron with inhomogeneous focusing magnetic field in which the klinotron effect is applied to improve the efficiency of energy exchange between the tubular electron beam and electromagnetic field of the open coaxial cavity is investigated. It is shown that in this device with double electron optics at f₀ = 100 GHz and at V₀ = 2,8 kV, B_0max ~ 0,4...0,436 T, B_0min = 0,266...0,338 T, I₀ = 3...10 A of relatively thick double electron beams (Δr/r₀ = 0,01) the efficiency 10... 18 % is achieved.

Simulation and experimental breadboarding of 35 GHz spatial harmonic magnetrons with cold cathode

An analytical estimation has been performed to determine the optimal parameters of pulsed magnetrons, operating at a spatial harmonic at a frequency of 35 GHz and an anode voltage of 6.5 kV in the drift-resonance mode, with the main cathode being the cold secondary-emission one. A 3D simulation experiment on a magnetron with the analytically determined characteristics has been conducted to check its adequacy in providing the required energy parameters. The breadboard magnetrons have the number of vane-type resonators in the anode unit N = 20 and N = 16, respectively. The both magnetrons have generated the electromagnetic radiation in the Ka range with the magnetic field being slightly above 0.4 T. It was proven that it is possible to create a full-functional Ka-range magnetron with a relatively low anode voltage and such parameters that enable its wide applicability.

Determination of the Upper Existence Domain of Operating Oscillation Modes in Space Harmonic Magnetrons

In the course of development work on designing millimeter-wavelength magnetrons, many attempts had been made to achieve the regime of interaction between an electron flow and a spatial harmonic of one of the doublet-type oscillation modes. The techniques for establishing the causes that restricted the extent of oscillation in modes for the magnetic field non-pi-mode magnetron and determining the criterion for the upper boundary of their existence from the magnetic field can be employed as an integrated approach to selecting an oscillatory system parameter and calculating the magnetrons operating conditions from the magnetic field magnitude. The aim of computations is to determine the interaction space parameters that provide the required extent of the active oscillation mode region of an appropriate efficiency. Here, a description is given of the procedure for selection and subsequent test calculations of slow-wave structure parameters in a magnetron analog.

3-B Simulation of Magnetrons Having a Secondary-Emission Cathode Stimulated by Electrons from a Field Emitter

The results are given of the 3-D simulation of the secondary-electro multiplication process in a magnetron with a cold secondary-emission cathode in which the primary electron sources are the blade-shaped field emitters. The application of the anode voltage pulse tandem is conducive to improving the efficiency and reliability of triggering the electromagnetic self-oscillation excitation in a magnetron oscillator, as the nanosecond radiation pulses are being generated

3D simulation of magnetrons with secondary-emission cathode stimulated by electrons from a field emitter

Presented in this paper are the results of 3-D simulation of the secondary-electro multiplication process in a magnetron with cold secondary emission Pd-Ba alloy cathode in which the primary electron sources are the blade-shaped field emitters. The application of the anode voltage pulse tandem is conducive to improving the efficiency and reliability of triggering the electromagnetic self-oscillation excitation in magnetron oscillator, as the nanosecond radiation pulses are generated.

The results of calculation of 0.18 THz klynoorbictron-amplifier

The results of the optimization search using an elaborated mathematical model for the promising versions of a klynoorbictron-amplifier design to be operated over the frequency range of 180 GHz are presented. The versions of the devices have been found, which are capable of providing from 10 to 14 % efficiency, the gain of 18-38 dB, the output power of 10 to 40 W with input signal power of 0.01-0.5 W at operating voltage of 0.07 - 0.18 A.