Calculations of three-dimensional frequency-domain nonlinear beam-wave reaction for helix traveling wave tubes

Abstract In this paper, two types of coaxial coupler and waveguide coupler for different frequency helix traveling wave tubes (TWTs) are designed, fabricated and cold tested. The coaxial coupler includes of window ceramic and RF transformer section. At present multi-section impedance transformer design approach is used for wideband helix TWTs. In any helix TWT, impedance of the source is transformed to the characteristic impedance of helix. This is done by the quarter-wavelength (λ/4) impedance transformation approach. The simulated results of different types of couplers are carried out by HFSS and CST microwave studio software and compare with experimental results. Three-dimensional electromagnetic field simulators allowing the any geometry with port excitations it is possible to model the complex coaxial and waveguide type couplers with helix SWS assembly and predict its desired return loss performances.

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Large-Signal Investigation of Cold and Hot Matched Coupled-Cavity Traveling-Wave Tubes

Frequenz ◽

10.1515/freq-2014-0118 ◽

2014 ◽

Vol 0 (0) ◽

Author(s):

Sascha Meyne ◽

Jean-François David ◽

Arne F. Jacob

Keyword(s):

Traveling Wave ◽

Characteristic Impedance ◽

Matching Condition ◽

Wave System ◽

Small Signal ◽

Large Signal ◽

Beam Wave ◽

Signal Approach ◽

Traveling Wave Tubes ◽

Coupled Cavity

AbstractThe implications of different matching conditions for coupled-cavity traveling-wave tubes are considered. Using a small-signal approach the characteristic impedance for the coupled (hot) beam-wave system is derived. It is taken as reference impedance to model ideal transformers and severs. This matching condition is compared to the standard cold match and both cases are analyzed using a large-signal interaction tool. The implications on input reflection and output gain are discussed.

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A three-dimensional finite-element thermal/mechanical analytical technique for high-performance traveling wave tubes

10.2514/6.1992-1824 ◽

1992 ◽

Author(s):

KURT SHALKHAUSER ◽

KAREN BARTOS ◽

E. FITE ◽

G. SHARP

Keyword(s):

Finite Element ◽

Traveling Wave ◽

High Performance ◽

Three Dimensional ◽

Analytical Technique ◽

Dimensional Finite Element ◽

Traveling Wave Tubes ◽

Three Dimensional Finite Element

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Nonlinear beam-wave interaction of terahertz two-beam folded waveguide traveling wave tube

2015 IEEE International Vacuum Electronics Conference (IVEC) ◽

10.1109/ivec.2015.7223975 ◽

2015 ◽

Author(s):

Ke Li ◽

Wenxin Liu ◽

Yong Wang ◽

Miaomiao Cao

Keyword(s):

Traveling Wave ◽

Wave Interaction ◽

Traveling Wave Tube ◽

Wave Tube ◽

Nonlinear Beam ◽

Beam Wave ◽

Folded Waveguide ◽

Beam Wave Interaction

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Genesis: a 2.5D nonlinear simulation code for helix traveling wave tubes in the frequency domain

IEEE Conference Record - Abstracts. 1999 IEEE International Conference on Plasma Science. 26th IEEE International Conference (Cat. No.99CH36297) ◽

10.1109/plasma.1999.829365 ◽

2003 ◽

Cited By ~ 2

Author(s):

H.P. Freund ◽

T.M. Antonsen ◽

B. Levush

Keyword(s):

Frequency Domain ◽

Traveling Wave ◽

Simulation Code ◽

Nonlinear Simulation ◽

Traveling Wave Tubes ◽

Genesis A

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Comparative study of envelope models for hybrid time- and frequency-domain simulation of traveling-wave tubes

International Journal of Microwave and Wireless Technologies ◽

10.1017/s1759078717001349 ◽

2018 ◽

Vol 10 (5-6) ◽

pp. 521-529

Author(s):

Djamschid Safi ◽

Philip Birtel ◽

Sascha Meyne ◽

Arne F. Jacob

Keyword(s):

Frequency Domain ◽

Traveling Wave ◽

Phase Transfer ◽

Hybrid Approach ◽

Traveling Wave Tube ◽

Transfer Factors ◽

Frequency Independent ◽

Tone Signal ◽

Traveling Wave Tubes ◽

Selection Of

A selection of hybrid frequency- and time-domain approaches is evaluated with respect to their suitability for predicting the multi-tone behavior of a reference Ku-band helix traveling-wave tube. For this, a frequency-domain code is extended by a selection of frequency-dependent and frequency-independent envelope models and compared to a number of simulated and measured responses to two-tone signal excitation with varying frequency spacing. The selected envelope methods are investigated both in the hybrid approach and based on measured TWT characteristics. Output levels and classical multi-tone metrics, such as intermodulation products and phase transfer factors, are considered. By reducing a modulation scenario to a number of significant sequences, a comparison to full physics-based frequency-domain simulation is presented to show the potential of the proposed approach.

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