A Simple Analysis of Helical Slow-Wave Structure Loaded by Dielectric Embedded Metal Segments for Wideband Traveling-Wave Tubes

Seshadri, R.; Ghosh, S. K.; Bhansiwal, A.; Kamath, Sudhir; Jain, P. K.

doi:10.2528/pierb10031201

Cited by 5 publications

(4 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although various components have been developed for THz applications [5][6][7][8][9][10][11][12][13][14][15][16][17][18], high power, low cost, and compact THz sources are not readily available [19]. With the rapid advancement of multi-physics based codes, which provide the possibility of simulating the nonlinear beam-wave interaction dynamics [20][21][22][23][24], extending the operating frequency of the existing microwave tube designs [25][26][27][28][29] has become a promising approach for developing compact and powerful THz sources [30][31][32][33][34][35][36]. In accordance with this approach, design and numerical simulations of a 140 GHz spatial-harmonic magnetron (SHM) with a maximum pulse-output power of about 11 kW is presented in this paper.…”

Section: Introductionmentioning

confidence: 99%

DESIGN AND 3-D PARTICLE-IN-CELL SIMULATION OF A 140 GHz SPATIAL-HARMONIC MAGNETRON

Esfahani¹,

Tayarani²,

Schunemann³

2013

PIER

View full text Add to dashboard Cite

Abstract-This paper discusses design procedure and 3-D numerical simulation of a 140 GHz spatial-harmonic magnetron (SHM). The well known scaling laws and an approximate approach based on single harmonic analysis are used to determine the interaction space dimensions and the optimum geometrical parameters of the side resonators. Numerical simulations of the SHM were performed using CST-Particle Studio. Since the simulations are not based on artificial RF priming or assuming restrictive assumptions on the mode of operation or on the number of harmonics to be considered, electromagnetic oscillations grow naturally from noise. The presented SHM shows stable operation in the π/2 − 1-mode at 140 GHz over a range of DC anode voltages extending from 11.3 kV to 11.5 kV and for an axial magnetic flux density equal to 0.79 T. Output power of the SHM varies from 2 kW to 11 kW over these voltages with a maximum efficiency of about 6.8%.

show abstract

Section: Introductionmentioning

confidence: 99%

DESIGN AND 3-D PARTICLE-IN-CELL SIMULATION OF A 140 GHz SPATIAL-HARMONIC MAGNETRON

Esfahani¹,

Tayarani²,

Schunemann³

2013

PIER

View full text Add to dashboard Cite

show abstract

“…The cold-test parameters for series of pitches were simulated by Ansoft HFSS which can get a credible result [17,18]. The optimization parameters were recorded in x and the initial variable was generated by randomly changing each parameter.…”

Section: Example Optimization Design Of a Space Twtmentioning

confidence: 99%

Numerical Optimization of Pitch Profile for Overall Efficiency Enhancement of a Space TWT

Yi¹,

Liu²,

Xiao³

2010

PIER C

View full text Add to dashboard Cite

Abstract-Obtaining higher efficiency during the development of space Traveling Wave Tubes (TWTs) is always one of the most important goals for scientists. In this paper, a scheme of obtaining the maximum theoretical overall efficiency is explored by optimizing the helix pitch profile of a TWT based on the collectability of spent beam. The collectability of the spent beam was evaluated by the maximum collector efficiency, and this maximum collector efficiency was employed to calculate the maximum theoretical overall efficiency. The energy distribution of the spent beam and the output power of TWTs were calculated by the 3-D large signal Beam-Wave Interaction Simulator (BWIS) of MTSS. The detailed design of a Ku-band helix TWT is described according to three optimization goals (theoretical overall efficiency, theoretical collector efficiency and electronic efficiency). The simulation results indicate that the optimization for high interaction circuit efficiency or collector efficiency by itself is not adequate to obtain maximum overall efficiency. The maximum theoretical overall efficiency of 77% was achieved via the optimization of slow wave structure for theoretical overall efficiency.

show abstract

“…The challenge for a sever design is to attenuate the forward wave over a wide range of frequencies and at the same time not letting the reflections to build up in the circuit. This needs an efficient impedance matching in the sever structure over a wide bandwidth [7,8]. Moreover, the classic sever is comprised of two separate ports loaded with loss material that attenuates the forward going wave and the reflected wave.…”

Section: Introductionmentioning

confidence: 99%

Mems Compatible Sever for 220 GHZ Ultra Wide Band Twta: Design and Particle-in-Cell Analysis

Baig

Barnett²,

Gamzina³

et al. 2013

PIER Letters

View full text Add to dashboard Cite

Abstract-We report a MEMS (micro-electro-mechanical systems) compatible distributed loss type sever design for the 220 GHz double vane half period staggered traveling-wave tube amplifier (TWTA) [1]. The cold test simulations for a full TWT model including input/output couplers and broadband tapered vane transitions incorporating the sever, predicted a return loss (S 11 ) of < −10 dB in the pass band (205 GHz-275 GHz) while an insertion loss/isolation (S 21 ) of ∼ −27 dB. The return loss of the TWT circuit did not degrade by the inclusion of the sever (< −10 dB) while still maintaining a good isolation (S 21 ) for the RF signal. Particle-In-Cell (PIC) simulation analysis for the full 220 GHz TWT circuit (a) without sever and (b) with sever was conducted. With the inclusion of the sever, the TWTA showed generally a stabilized output response for all cases. The maximum power from the long sever case was ∼ 25 W for P in ∼ 50 mW and the gain was ∼ 27 dB. The reverse power was decreased to ∼ 30 mW. For the short sever, the PIC results were even better with a maximum output power of ∼ 62 W and a gain of ∼ 30.92 dB with a reduced reverse power of ∼ 5 mW for an input power of 50 mW at 220 GHz. The FFT spectrum of the RF signal at the output port also showed a spectrally pure waveform at 220 GHz.

show abstract

A Simple Analysis of Helical Slow-Wave Structure Loaded by Dielectric Embedded Metal Segments for Wideband Traveling-Wave Tubes

Cited by 5 publications

References 17 publications

DESIGN AND 3-D PARTICLE-IN-CELL SIMULATION OF A 140 GHz SPATIAL-HARMONIC MAGNETRON

DESIGN AND 3-D PARTICLE-IN-CELL SIMULATION OF A 140 GHz SPATIAL-HARMONIC MAGNETRON

Numerical Optimization of Pitch Profile for Overall Efficiency Enhancement of a Space TWT

Mems Compatible Sever for 220 GHZ Ultra Wide Band Twta: Design and Particle-in-Cell Analysis

Contact Info

Product

Resources

About