Increase in the energy efficiency of a pulsed-periodic relativistic backward wave oscillator with a modulating resonant reflector

Totmeninov, E. M.; Выходцев, П. В.; Gunin, A. V.; Klimov, A. I.; Rostov, V. V.

doi:10.1134/s1063784214030268

Cited by 26 publications

(10 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Within the stationary stage of the oscillation (10-100 ns), the simulated microwave power ranged from 600 to 630 MW at the efficiency range of 30%-34%. For example, for the relativistic Cherenkov backward wave oscillator (RBWO) with a thin annular electron beam, the simulated duration of stably efficient (≈30%) stationary oscillation was limited to ∼50 ns [7].…”

Section: Numerical Experimentsmentioning

confidence: 99%

“…Enlargement of the e-beam cross section should facilitate the conditions for the long-pulse generation [6], when the growth of a transverse dimension of the beam becomes essential due to the cathode plasma expansion (the expansion velocity across the magnetic field lines is ∼10 6 cm/s) [5] as well. In Cherenkov microwave oscillators, where a thin tubular beam is used, a transverse expansion of the cathode plasma results in the deterioration of the terms of current transport through a slow-wave structure (SWS) and does not contribute to the conservation of the optimum conditions of the energy exchange throughout the duration of the current pulse [7].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

<inline-formula> <tex-math notation="TeX">\(X\) </tex-math></inline-formula>-Band Relativistic Cherenkov Microwave Oscillator With Increased Cross-Sectional Electron Beam

Totmeninov

2014

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

Based on numerical simulation, a scheme of the X-band relativistic Cherenkov microwave oscillator with a hollow cylindrical increased cross-sectional electron beam transported by the external magnetic field is considered. For the electron energy of ∼0.5 MeV and electron beamwidth of ∼5 mm, an effective 100-ns-long pulse mode in a reduced magnetic field of 0.75 T has been calculated. Within the stationary stage of oscillation, the maximum simulated microwave power for the operating TM 01 mode was 630 MW that corresponded to the oscillator efficiency of 34% at the oscillation frequency of 10 GHz.

show abstract

Section: Numerical Experimentsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

<inline-formula> <tex-math notation="TeX">\(X\) </tex-math></inline-formula>-Band Relativistic Cherenkov Microwave Oscillator With Increased Cross-Sectional Electron Beam

Totmeninov

2014

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

show abstract

“…The relativistic backward wave oscillator (RBWO) is considered to be one of the most promising high power microwave (HPM) generators due to its compact structure [1], [2], high conversion efficiency [3], [4], high tunability [5], [6] and the ability of repetitive-rate operation [7], [8]. As the high power microwave (HPM) technology has matured gradually [9], [10], increasing the output power in the low magnetic field has been a leading tendency in the development of RBWO [11]- [14], especially when the generated wavelength goes into high frequency range such as Ka-band [15], [16].…”

Section: Introductionmentioning

confidence: 99%

“…Second, the low guide magnetic field is likely to weaken the confinement of the electron beam. Thus small quantities of the electron may bombard on the inner surface of the corrugated waveguide [1], [8].…”

Section: Introductionmentioning

confidence: 99%

Theoretical Research on Properties of Spatial Harmonics in Corrugated Waveguide

Teng

Wang

et al. 2019

IEEE Access

View full text Add to dashboard Cite

This paper investigates the dependence of the properties of the spatial harmonics on the overmoded ratio of the corrugated waveguide operating in TM 01 at 30 GHz with the consideration of the effects of the ripple shape. It is found that as the overmoded ratio grows, the electric fields concentrate towards the ripple surface, which weakens the enhancement of the power handling capacity caused by augmentation of the overmoded ratio. As the overmoded ratio grows, the ratio between the field amplitudes of the −1st spatial harmonic and the fundamental harmonic increases monotonically. Therefore, the total electric fields composed of the spatial harmonics become the spatial beating-wave with the single frequency, whose amplitudes vary along z-axis with the spatial period determined mainly by the −1st spatial harmonic and the fundamental harmonic. Researches on coupling impedances show that with the same overmoded ratio, the corrugated waveguide consisting of the improved rectangular ripples provides better synchronous coupling for the wave-beam interaction than that of the sinusoidal ripples does. Moreover, it is better to choose the fundamental harmonic close to the light line as the synchronous wave for the wave-beam interaction in the low magnetic field. In that case, even if the electron beam keeps far away from the ripple surface, the synchronous wave still provides strong enough coupling for the electron beam. INDEX TERMS Corrugated waveguide, coupling impedance, field distribution, high power microwave generation, overmoded ratio.

show abstract

“…Analogously to [10], radial expansion of cathode plasma can lead to deterioration of the conditions of energy exchange of the electron beam and electro magnetic field (the beam current increases while diode voltage decreases during the pulse) and the passage of current through the space of interaction. Another rea son can be related to the development of an explosive electron emission on the surface of electrodynamic structure under the influence of intense high fre quency fields, which leads to suppression or even ces sation of generation [11].…”

mentioning

confidence: 99%

On the radiation phase stability of a relativistic coaxial backward-wave oscillator at decimeter wavelengths

et al. 2015

Self Cite

View full text Add to dashboard Cite

creating multichannel systems consisting of one type parallel devices excited by a common power supply. As a result, it is possible to obtain strong directional radiation with an increasing maximum density of power flux being proportional to N 2 , where N is the number of elements in the system. The possibility of obtaining a stable phase of micro wave radiation (from pulse to pulse) achieved at a suf ficiently rapid growth of voltage U(t) across the diode forming the beam has been proven in the case of a rel ativistic backward wave oscillator (RBWO) with an electrodynamic system based on a round corrugated wave guide [1]. This system operates in the mode of superhigh radiance at a carrying frequency of 3.7 GHz and a relatively short microwave pulse of 3 ns. Stability of the radiation phase was also observed in the RBWO experiments at frequencies of 10 [2, 3] and 37 GHz [4,5]. Special devices were used in these experiments in obtaining a sharper front of voltage pulse in order to satisfy the theoretical condition of phase stabilization [5,6] (1)where T is the period of high frequency oscillations and C = [eI 0 Z/(2mc 2 )] 1/3 is the generalized Pierce parameter. In the latter formula, I 0 is the amplitude of an electron beam current; Z is its connective resistance with synchronous harmonics of the operating wave; e and m are the electron charge and mass, respectively; and γ 0 is the relativistic factor relating to diode voltage amplitude U 0 . Temporal factor T U is determined through the maximal derivative at the front of the volt age pulse and its amplitude,When condition (1) is satisfied, the growth duration of the beam current determined analogously to (2) cer tainly has a lesser magnitude [5]. The spectral compo nents from the front of a current then have weakly vari able phases in the frequency band of interaction [6]. Therefore, condition (1) is necessary when obtaining a fixed initial phase (ϕ in = const) of the microwave radi ation pulse from one pulse to another. For excitation of parallel generators, this phase should be the same in each pulse. With allowance for possible frequency deviation δω (ω is the carrying frequency) during time τ m from pulse to pulse, it is necessary to satisfy the con ditions (3) where δϕ in is the initial phase instability [5]. Due to the relativistic energy dependence of the electron velocity at small variations of the amplitude of pulse voltage (δU 0 /U 0 < 1%), conditions (3) can be fulfilled if the shape of the pulse is reproduced quite stable.In contrast to [1][2][3][4][5], the main aim of this work is to verify the possibility of the phase stabilization of microwave radiation in experiments with a generator frequency of 1-2 GHz and pulse duration τ m = 100T and without making the voltage impulse front sharper. In a frequency range of 1-2 GHz, it is worthwhile to use the RBWO construction based on a coaxial delay system (CRBWO) [7]. This is caused by the small dimensions of the electrodynamic system of the gen erator (D/λ < 1, L = 1.5λ, where D and L are the aver age di...

show abstract

Increase in the energy efficiency of a pulsed-periodic relativistic backward wave oscillator with a modulating resonant reflector

Cited by 26 publications

References 9 publications

<inline-formula> <tex-math notation="TeX">\(X\) </tex-math></inline-formula>-Band Relativistic Cherenkov Microwave Oscillator With Increased Cross-Sectional Electron Beam

<inline-formula> <tex-math notation="TeX">\(X\) </tex-math></inline-formula>-Band Relativistic Cherenkov Microwave Oscillator With Increased Cross-Sectional Electron Beam

Theoretical Research on Properties of Spatial Harmonics in Corrugated Waveguide

On the radiation phase stability of a relativistic coaxial backward-wave oscillator at decimeter wavelengths

Contact Info

Product

Resources

About