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Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)最新文献

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Phase noise reduction techniques of radar's TWTA 雷达TWTA相位降噪技术
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316223
Jae Seung Lee, N. Luhmann
{"title":"Phase noise reduction techniques of radar's TWTA","authors":"Jae Seung Lee, N. Luhmann","doi":"10.1109/IVELEC.2004.1316223","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316223","url":null,"abstract":"The reduction of phase noise of TWTAs in radar transmitters is imperative because strongly reflected clutter can mask the signal of a moving target. This paper provides better understanding of the phase noise behavior of a TWTA and proposes two new methods to substantially suppress this noise. Multi-PSK digital communication and modern radar transmitters have stringent requirements on their power amplifier amplitude and phase stability response. The TWTA in radar systems is operating at fully saturated power, causing the phase noise to be the dominant noise component. We propose two novel methods that can be complementary to further reduce the overall phase noise. These methods are superior to the present complicated noise filtering devices because of their simple implementation, lightness and inexpensiveness.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131052404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Use of state of the art computer-aided design tools at CPI 使用最先进的计算机辅助设计工具在CPI
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316235
R. Begum, J. Atkinson, M. Cattelino, J. Cusick, F. Friedlander, J. Legarra, B. Stockwell, E. Wright
{"title":"Use of state of the art computer-aided design tools at CPI","authors":"R. Begum, J. Atkinson, M. Cattelino, J. Cusick, F. Friedlander, J. Legarra, B. Stockwell, E. Wright","doi":"10.1109/IVELEC.2004.1316235","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316235","url":null,"abstract":"This paper presents results from some of the tools currently used at CPI for design of helix TWTs, coupled-cavity TWTs and klystrons. HFSS, a commercial 3D electromagnetic code, and CTLSS, a 3D electromagnetic code, are currently used to predict helix circuit dispersion and impedance characteristics. CTLSS and HFSS are the first tools available that allow us to perform completely cold-test-free helix TWT design. HFSS is also used to predict CC-TWT circuit dispersion characteristics and to design waveguide transformers, windows and severs.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130275827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Development of Terahertz backward wave oscillators 太赫兹反向波振荡器的研制
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316201
L. Ives, C. Kory, M. Read, J. Neilson, M. Caplan, N. Chubun, R. Wilcox, T. Robinson
{"title":"Development of Terahertz backward wave oscillators","authors":"L. Ives, C. Kory, M. Read, J. Neilson, M. Caplan, N. Chubun, R. Wilcox, T. Robinson","doi":"10.1109/IVELEC.2004.1316201","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316201","url":null,"abstract":"Summary form only given. Calabazas Creek Research, Inc.is funded by NASA to develop efficient, light-weight, backward wave oscillators (BWOs) for applications from 300 GHz to 1.5 THz. These devices are needed as local oscillator sources in heterodyne receivers. Above 100 GHz, only BWOs have broad tunability (over 100 GHz) and high output power (/spl sim/1 mW); however, existing sources are heavy, consume excessive power, require water cooling, and have poor output mode purity. The technical objectives of the current program are as follows: incorporate a depressed collector to improve the efficiency and eliminate water cooling; improve the electron gun and configuration of the circuit to increase interaction efficiency; improve the output coupling to increase mode purity; and reduce the magnet system size and weight. A solid model of the final BWO configuration is detailed in this paper. The BWO operates in a 1.1 Tesla, flat magnetic field provided by a permanent magnet. The device operates at 3000-6000 V and is predicted to produce 6-8 mW of RF power continuously from 600-700 GHz.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130834932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 12
Operation and performance of a 3D finite element charged particle code with adaptive meshing [electron gun design] 自适应网格三维有限元带电粒子代码的运行与性能[电子枪设计]
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316338
L. Ives, T. Bui, W. Vogler
{"title":"Operation and performance of a 3D finite element charged particle code with adaptive meshing [electron gun design]","authors":"L. Ives, T. Bui, W. Vogler","doi":"10.1109/IVELEC.2004.1316338","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316338","url":null,"abstract":"Summary form only given. Beam optics analysis (BOA), a new, 3D charged particle program is available and in use for the design of complex, 3D electron guns. BOA incorporates both electrostatic and magnetostatic field solvers. The electrostatic solver is based on the standard nodal finite element method. The magnetostatic field solver is based on the vector finite element method and is also called during the trajectory simulation process to solve for self magnetic fields. This presentation describes code operation, presents examples and test case results, and describes future developments.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"215 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124226462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Fast simulation of electromagnetic slow-wave structures 电磁慢波结构的快速仿真
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316342
S. Cooke, B. Levush, A. Vlasov, T. Antonsen
{"title":"Fast simulation of electromagnetic slow-wave structures","authors":"S. Cooke, B. Levush, A. Vlasov, T. Antonsen","doi":"10.1109/IVELEC.2004.1316342","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316342","url":null,"abstract":"We present results of a model for fast end-to-end simulation of extended slow-wave structures, which obtains a similarly reduced representation for Maxwell's equations directly from 3-D numerical simulations of individual cavities (cells) of the structure. We will demonstrate that our method retains the advantages of the equivalent circuit models, but with the accuracy of a full 3-D simulation that normally would be impractical. In addition, the method provides the complete 3-D electromagnetic field structure, that may be used to compute interactions with an electron beam using a large-signal simulation code such as TESLA.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128814583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A study of the inter-diffusion of tungsten and osmium-ruthenium in M-cathodes and the effects on performance and life 钨和锇钌在m阴极中的互扩散及其对性能和寿命影响的研究
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316359
L. Falce
{"title":"A study of the inter-diffusion of tungsten and osmium-ruthenium in M-cathodes and the effects on performance and life","authors":"L. Falce","doi":"10.1109/IVELEC.2004.1316359","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316359","url":null,"abstract":"M type cathodes have become the most widely used electron sources for microwave vacuum electron devices such as klystrons and travelling wave tubes. These cathodes are barium calcium aluminate impregnated porous tungsten over coated with 5000 /spl Aring/ of osmium ruthenium. The advantages of this type of cathode are the ability to achieve over two times higher current densities at the same temperature as an uncoated, impregnated porous tungsten cathode or achieving the same current at between 75 and 100/spl deg/C lower temperatures. The latter can result in eight times longer life expectancy. A concern among users is the permanency of the osmium ruthenium coating. This study reveals that from the very beginning of life that tungsten does diffuse to the emitting surface. However instead of a deterioration of performance with time as a result of this activity an improvement is actually achieved. Data is presented showing the effects of the diffusion on the tungsten surface concentration. Auger depth profiling is used to demonstrate the phenomenon. Data is presented for the initial status after cathode activation, after 33,517 hours of aging at 1000/spl deg/C and after 53,142 aging at 1000/spl deg/C. Data will also be presented showing surface tungsten concentration versus aging time at different temperatures.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121658725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
MM-wave source development at Los Alamos 洛斯阿拉莫斯的毫米波源开发
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316179
B. Carlsten, S. Russell, L. Earley, J. Potter, P. Ferguson, S. Humphries
{"title":"MM-wave source development at Los Alamos","authors":"B. Carlsten, S. Russell, L. Earley, J. Potter, P. Ferguson, S. Humphries","doi":"10.1109/IVELEC.2004.1316179","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316179","url":null,"abstract":"Summary form only given. A sheet-beam traveling-wave amplifier has been proposed as a high-power generator for RF from 95 to 300 GHz, using a microfabricated RF slow-wave structure. The planar geometry of microfabrication technologies matches well with the nearly planar geometry of a sheet beam, and the greater allowable beam current leads to high-peak power (up to 500 kW at 95 GHz), high-average power (up to 5 kW), and wide bandwidths (up to 10%). Simulations have indicated gains in excess of 1 dB/mm, with extraction efficiencies greater than 20%.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126146019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 11
Peer-peer phase-locking of two L-band industrial heating magnetrons 两个l波段工业加热磁控管的对等锁相
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316286
K.G. Kato, K. Brown, D. D. Crouch, G.K. Jones, R. Mcdonald, A. Wynn, D. Blank, P.S. Campbell, R. Lentz, R. Meredith
{"title":"Peer-peer phase-locking of two L-band industrial heating magnetrons","authors":"K.G. Kato, K. Brown, D. D. Crouch, G.K. Jones, R. Mcdonald, A. Wynn, D. Blank, P.S. Campbell, R. Lentz, R. Meredith","doi":"10.1109/IVELEC.2004.1316286","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316286","url":null,"abstract":"We demonstrate the peer-peer phase-locked operation of two matched industrial heating magnetrons. Two commercial off-the-shelf California Tube Laboratory model CWM-75L industrial heating magnetrons were \"cherry picked\" for identical operating voltage (17.5 kV), current (5.0 A), operating frequency (915 MHz), and output power (75 kW). Their microwave power outputs were cross-coupled by means of a four-port branch wall directional coupler and phase shifter. Coupling as low as -20 dB of each other's output powers was sufficient to create mutual locked operation between both magnetrons. These results suggest more than two matched magnetrons may be driven in a phased-locked condition.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126033798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
High power mini-TWT development at L-3 Communications L-3通信公司大功率小型行波管的发展
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316321
R. Watkins
{"title":"High power mini-TWT development at L-3 Communications","authors":"R. Watkins","doi":"10.1109/IVELEC.2004.1316321","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316321","url":null,"abstract":"Summary form only given. This paper provides a hardware-centered status on the progress over the last year in extending wideband mini-TWT performance to 200 W. Over the least year, L-3 has completed two designs demonstrating 200 to 400 W CW over more than an octave, with peak efficiencies of nearly 50% using only a three-stage collector. The mini-TWT gun assembly shares common parts with production TWTs while only requiring a new cathode and beam-forming electrode. The cathode current density is less than 2 A/cm/sup 2/, which results in exceptionally long life. The higher beam perveance of the mini-TWT design allows for wide band operation with good power flatness. This talk presents experimental data and challenges overcome on recent high power designs.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127324546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
CNT electron source with uniform emission distribution 具有均匀发射分布的CNT电子源
Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786) Pub Date : 2004-04-27 DOI: 10.1109/IVELEC.2004.1316301
S. Nakata, T. Sawada, F. Abe, M. Fujikawa, A. Hosono, T. Shiroishi, K. Nishimura, S. Kawamoto, S. Watanabe, T. Yamamuro, Z. Shen, S. Horibata, S. Okuda, K. Oono, Y. Hirokado
{"title":"CNT electron source with uniform emission distribution","authors":"S. Nakata, T. Sawada, F. Abe, M. Fujikawa, A. Hosono, T. Shiroishi, K. Nishimura, S. Kawamoto, S. Watanabe, T. Yamamuro, Z. Shen, S. Horibata, S. Okuda, K. Oono, Y. Hirokado","doi":"10.1109/IVELEC.2004.1316301","DOIUrl":"https://doi.org/10.1109/IVELEC.2004.1316301","url":null,"abstract":"The carbon nanotube (CNT) has been well known as a good field emission material by its superior structure, such as small radius and high aspect ratio. It has also been said that a large sized cathode plate can be easily fabricated at low cost by a CNT paste printing technique. However, the CNT has a cohesive characteristic in its nature and the printed layer becomes a rugged surface if an ordinal dispersant is used. The surface roughness impedes field uniformity on the CNT layer and leads to degradation of the emission uniformity. In the following, we describe the techniques used to fabricate a smooth CNT layer and to activate the layer for good emission uniformity. To suppress the cohesion of CNT in the paste, we applied newly developed dispersive materials. After printing the paste, a surface roughness (Ra) of less than 0.2 /spl mu/m was achieved.","PeriodicalId":283559,"journal":{"name":"Fifth IEEE International Vacuum Electronics Conference (IEEE Cat. No.04EX786)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129157333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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