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Performance Of A Two-pump Fiber Optical Parametric Amplifier In A 10 Gb/s × 64 Channel Dense Wavelength Division Multiplexing System
No full textWe analyze the performance of two-pump fiber optical parametric amplifiers (2P-FOPA) as preamplifiers for wavelength division multiplexing transmission systems. We simulate the propagation of 10 Gb/s × 64 channels over 120 km of non-zero dispersion shifted fiber and amplify them by a 2P-FOPA before detection. We demonstrate that a careful design of the FOPA parameters leads to high system performance, comparable than those obtained with erbium and Raman amplifiers. For signal powers of -32.5 dBm at the FOPA input we observe clear eye openings for all the amplified signal lasers, with an average gain of 22 dB and low ripple (6 dB) over 25 nm bandwidth. We study the influence of fluctuations of the zero dispersion wavelength of the FOPA fiber. These fluctuations in realistic fibers tend to reduce the average gain and degrade the noise figure and spectral gain ripple. © 2003 Elsevier Science B.V. All rights reserved.21804/06/15303310Marhic, M.E., Kagi, N., Chiang, T.-K., Kazovsky, L.G., (1996) Opt. Lett., 21, p. 573Imajuku, W., Takada, A., Yamabayashi, Y., (1999) Electron. Lett., 22, p. 1954Imajuku, W., Takada, A., Yamabayashi, Y., (2000) Electron. Lett., 36, p. 63Watanabe, S., Takeda, S., Chikama, T., (1998) IOOC/ECOC'98, p. 83. , PD PaperStolen, R.H., Bjorkholm, J.E., (1982) IEEE J. Quantum Electron., QE-18, p. 1062Hansryd, J., Andrekson, P., (2001) IEEE Photon. Technol. Lett., 13, p. 194Kagi, N., Chiang, T.K., Mahric, M.E., Kazovsky, L.G., (1995) Electron. Lett., 31, p. 1935Inoue, K., Mukai, T., (2001) Opt. Lett., 26, p. 10DeMatos, C.J.S., Chestnut, D.A., Reeves-Hall, P.C., Taylor, J.R., (2001) Opt. Lett., 26, p. 1583Ho, M.C., Uesaka, K., Marhic, M., Akasaka, Y., Kazovsky, L.G., (2001) J. Ligthwave Technol., 19, p. 977Blows, J.L., French, S.E., (2002) Opt. Lett., 27, p. 491Chavez Boggio, J.M., Grosz, D.F., Guimarães, A., Fragnito, H.L., (1999) Microw. Opt. Technol. Lett., 23, p. 318Cappellini, G., Trillo, S., (1991) J. Opt. Soc. Am. B, 8, p. 824Marhic, M.E., Park, Y., Yang, F.S., Kazovsky, L.G., (1996) Opt. Lett., 21, p. 1354Wong, K.K.Y., Marhic, M.E., Uesaka, K., Kazovsky, L.G., (2002) IEEE Photon. Technol. Lett., 14, p. 911Yang, F.S., Ho, M.C., Marhic, M.E., Kazovsky, L.G., (1997) Electron. Lett., 33, p. 1812Chavez Boggio, J.M., Callegari, F.A., Tenenbaum, S., Rosolem, J.B., Barros, M.R.X., Fragnito, H.L., (2002) Optical Fiber Communication Conference, OFC'2002, , OSA Technical Digest, paper WGG-18, Optical Society of America, Washington, DCRadic, S., Mc Kinstrie, C.J., Chraplyvy, A.R., Raybon, G., Centanni, J.C., Jorgensen, C.G., Brar, K., Headley, C., (2002) Optical Fiber Communication Conference, OFC'2002, , OSA Technical Digest, PD FB5, Optical Society of America, Washington, DCChavez Boggio, J.M., Tenenbaum, S., Fragnito, H.L., (2001) J. Opt. Soc. Am. B, 18, p. 1428Chavez Boggio, J.M., Tenenbaum, S., Fragnito, H.L., (2001) Optical Fiber Communication Conference, OFC'2001, , OSA Technical Digest, paper WDD24, Optical Society of America, Washington, DCHo, M.-Ch., Marhic, M.E., Wong, K.Y.K., Kazovsky, L.G., (2002) J. Ligthwave Technol., 20, p. 469Desurvire, E., (1994) Erbium-doped Fiber Amplifiers: Principles and Applications, , New York: WileyAgrawal, G.P., (1995) Nonlinear Fiber Optics, Second Ed., , New York: Academic PressLaming, R.I., Gnauck, A.H., Gilles, C.R., Zervas, M.N., Payne, D.N., (1992) IEEE Photon. Technol. Lett., 4, p. 1348Karlson, M., (1998) J. Opt. Soc. Am. B, 15, p. 2269Eiselt, M., Jopson, R.M., Stolen, R.H., (1997) J. Ligthwave Technol., 15, p. 135Gripp, J., Mollenauer, L.F., (1998) Opt. Lett., 23, p. 1603Suzuki, H., Ohteru, S., Takachio, N., (1999) IEEE Photon. Technol. Lett., 11, p. 167
Demonstration Of 26 Db On-off Gain Of A Two-pump Fiber Optical Parametric Amplifier
No full textTwo-pump fiber optical parametric amplifier (FOPA) having ≅26 dB on-off gain with ±1.5 dB ripple over 30 nm bandwidth was demonstrated. An on-off gain >0 dB was obtained over 50 nm. By removing Fabry-Perot filter the noise was also amplified and depleted the pumps when pump power was greater that 120 mW.70636637Hansryd, J., Andrekson, P., Broadband CW pumped fiber optical parametric amplifier with 49 dB gain and wavelength conversion efficiency (2000) PD3, Optical Fiber Communications Conference, , Baltimore, USAMarhic, M.E., Park, Y., Yang, F.S., Kazovsky, L.G., Broadband fiber-optical parametric amplifiers and wavelength converters with low-ripple Chebyshev gain spectra (1996) Opt. Lett., 21, pp. 1354-1356Yang, F.S., Ho, M.C., Marhic, M.E., Kazovsky, L.G., Demonstration of two-pump fibre optical parametric amplification (1997) Electron. Lett., 33, pp. 1812-1813Boggio, J.M.C., Tenenbaum, S., Fragnito, H.L., Four wave mixing induced changes in the noise spectrum in an optical fiber (2001) WDD24, Optical Fiber Communications Conference, , Anaheim, US
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Mixing Of Signals In Two-pump Fiber Optic Parametric Amplifiers
No full textWe measure the parasitic four wave mixing tones generated by two signals that are amplified in two-pump fiber optical parametric amplifiers (2P-FOPAs). We consider two parametric amplifiers that use different lengths of fiber and pump powers but have identical parametric gain. We observe that the parasitic tones are stronger in the 2P-FOPA with longer fiber and smaller pump power. This is in agreement with our prediction of crosstalk in 2P-FOPAs.567569Marhic, M.E., Kagi, N., Chiang, T.-K., Kazovsky, L.G., Broadband fiber optical parametric amplifiers (1996) Opt. Lett., 21, pp. 573-575Marhic, M.E., Park, Y., Yang, F.S., Kazovsky, L.G., Broadband fiber optical parametric amplifiers and wavelength converters with low-ripple Chebyshev gain spectra (1996) Opt. Lett., 21, pp. 1354-1356Yang, F.S., Ho, M.C., Marhic, M.E., Kazovsky, L.G., Demonstration of two-pump fibre optical parametric amplification (1997) Electron. Lett., 33, pp. 1812-1813Chavez Boggio, J.M., Callegari, F.A., Tenenbaum, S., Rosolem, J.B., Barros, M.R.X., Fragnito, H.L., Demonstration of 26 dB on-off gain of a two-pump fiber optical parametric amplifier (2002) Optical Fiber Communication Conference, OFC'2002, , OSA Technical Digest (Optical Society of America, Washington, DC), paper WGG-18Radic, S., McKinstrie, C.J., Chraplyvy, A.R., Raybon, G., Centanni, J.C., Jorgensen, C.G., Brar, K., Headley, C., New Class of Continuous Wave Parametric Amplifiers (2002) Optical Fiber Communication Conference, OFC'2002, , OSA Technical Digest (Optical Society of America, Washington, DC), Post-Deadline paper, FB5Hansryd, J., Andrekson, P.A., Broad-Band Continuous-Wave-Pumped Fiber Optical Parametric Amplifier with 49-dB Gain and Wavelength-Conversion Efficiency (2001) IEEE Photon. Technol. Lett., 13, pp. 194-196Chavez Boggio, J.M., Tenenbaum, S., Fragnito, H.L., Amplification of broadband noise pumped by two lasers in optical fibers (2001) J. Opt. Soc. Am. B, 18, pp. 1428-1435Chavez Boggio, J.M., Dainese, P., Fragnito, H.L., Performance of a two-pump fiber optic parametric amplifier in a 10 Gb/s × 64 channel dense wavelength division multiplexing system (2003) Opt. Commun., 218, pp. 303-310Callegari, F.A., Chavez Boggio, J.M., Fragnito, H.L., Crosstalk mitigation in fiber optic parametric amplifiers Laser and Electro-optics Society Annual Meeting, LEOS 2002, pp. 383-384. , conference proceedings, WB3Agrawall, G.P., (2001) Nonlinear Fiber Optics, p. 49. , Academic Pres
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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