5 results
Phase nonlinearity reduction of a complex receiver having multiple phase correlators
- Mahadev Sarkar, B. R. Raghu, R. Sivakumar
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- Journal:
- International Journal of Microwave and Wireless Technologies / Volume 15 / Issue 10 / December 2023
- Published online by Cambridge University Press:
- 16 May 2023, pp. 1717-1730
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This article analyzes and describes phase nonlinearity reduction techniques in detail for ultra wideband complex receivers to qualify airborne system requirements. Phase nonlinearity directly affects the final frequency resolution coming from unknown threats. Thereby, the reduction of phase nonlinearity of all radio frequency (RF) channels including phase correlators is very essential. A simple phase nonlinearity calculation step has been shown in this article without taking the help of any coding (software). A detail excel sheet–based phase nonlinearity calculation has been explained and estimated with examples. Power and phase corrections are especially done to keep the RF response flat over a wide frequency spectrum to enhance better phase linearity. This is done by designing various equalizers with different slope gradients and adjusting power levels by using attenuation pads or reducing feeds by other means. Phase nonlinearity has been kept under control by tracking the phase of mixers, other passive/active components within ±5°, and all the RF channels within ±15°. The power level has been adjusted within P1dB or just beyond the P1dB to keep the harmonic level less, which in turn controls phase nonlinearity in all the active devices. The performance of phase correlators against various power levels has been analyzed to finalize uniform RF and LO power levels (feed) at the input of the phase correlators. The level of uniform feed has been decided after reviewing phase nonlinearity responses of the correlators. Thus, the final resolved frequency become accurate (<3 MHz root mean square). Finally, four receivers have successfully been developed and evaluated over temperature (−40°C to +71°C) and vibration to establish the method for mass production.
Population structure, genetic diversity and bakanae disease resistance among rice varieties
- S. Raghu, M. S. Baite, M. K. Yadav, S. R. Prabhukarthikeyan, U. Keerthana, C. Anil Kumar, B. Jeevan, S. Lenka, H. N. Subudhi, P. C. Rath
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- Journal:
- Plant Genetic Resources / Volume 20 / Issue 5 / October 2022
- Published online by Cambridge University Press:
- 30 March 2023, pp. 319-327
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Availability of resistance sources among cultivated varieties helps in easy utilization as donor owing to no deleterious linkage drag. In the present investigation, 121 rice varieties were screened for their resistance against a virulent isolate of Fusarium fujikuroi (Ff-10) and genotyped using reported microsatellite markers. Among 121 varieties, only eight varieties, namely Luna Sankhi, Improved Tapaswini, Sarasa, Sadabahar, CR-311, Kshira, Wifa-10 and Binadhan-8, were found to be highly resistant (HR), seven varieties were resistant (R), 31 were moderately resistant (MR), 10 were moderately susceptible (MS), 11 were susceptible (S) and the rest 54 were highly susceptible (HS). The allele diversity of molecular markers classified the population into three clusters. The highly resistant varieties were grouped in major clusters II and III, whereas the remaining genotypes were distributed in all three clusters. Analysis of molecular variance (AMOVA) resulted in 95% of the maximum diversity within the test population and 5% diversity between populations. Population structure analysis grouped the genotypes into two sub-populations based on relatedness, where most of the resistant genotypes were grouped into one sub-population and other genotypes were distributed among sub-populations. Re-examination of reported markers' trait associations with bakanae resistance in the experimental population identified marker RM-3698 as associated with resistance accounting 8.4% explained phenotypic variation. This study shows that simple sequence repeat markers can be used to assess allelic diversity and population structure of bakanae resistance in rice varieties. The highly resistant genotypes, along with resistance markers, could be used as donors in marker-assisted bakanae improvement breeding programmes.
Contributors
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- By Peter J. D. Andrews, Sandeep Ankolekar, Issam A. Awad, Omar Ayoub, Philip Bath, Jürgen Bardutzky, Alexander Beck, Patrícia Canhão, J. Ricardo Carhuapoma, Winward Choy, Mahua Dey, Rajat Dhar, Michael C. Diringer, Arnd Dörfler, Joshua R. Dusick, Justin A. Dye, Corina Epple, José M. Ferro, Reiner Fietkau, Anthony Frattalone, Philippe Gailloud, Oliver Ganslandt, Anil Gholkar, Philipp Gölitz, Barbara A. Gregson, Daniel Hanley, Thomas M. Hemmen, Dan Holmes, Hagen B. Huttner, Jennifer Jaffe, Olav Jansen, Eric Jüttler, Karl L. Kiening, Martin Köhrmann, Rainer Kollmar, Kara L. Krajewski, Joji B. Kuramatsu, Perttu J. Lindsberg, Andrew Losiniecki, Patrick Lyden, Neil A. Martin, Heinrich P. Mattle, A. David Mendelow, Patrick Mitchell, Daniel T. Nagasawa, Neeraj S. Naval, Jan-Oliver Neumann, Tim Nowe, Berk Orakcioglu, Soenke Peters, Sara Pitoni, François Proust, Adnan I. Qureshi, Martin Radvany, Elise Rowan, Tiina Sairanen, Oliver W. Sakowitz, Edgar Santos, Peter D. Schellinger, Stefan Schwab, Günter Seidel, Sabine Semrau, Louise Sinclair, Dimitre Staykov, Thorsten Steiner, Jeanne Teitelbaum, Wondwossen G. Tekle, Andreas W. Unterberg, Katayoun Vahedi, H. Bart van der Worp, Paul M. Vespa, Raghu Vindlacheruvu, Jens Witsch, Isaac Yang, Wendy C. Ziai, Mario Zuccarello, Klaus Zweckberger
- Edited by Stefan Schwab, Daniel Hanley, A. David Mendelow
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- Book:
- Critical Care of the Stroke Patient
- Published online:
- 05 June 2014
- Print publication:
- 05 June 2014, pp viii-xii
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- By Luis G. Acevedo, Schahram Akbarian, Ioanna Andreou, Krishnarao Appasani, Raghu K. Appasani, Julia Arand, David M. Ashley, Alexander R. Ball, Yehudit Bergman, Marina Bibikova, Angela Bithell, Francesca Bonafè, Eric E. Bouhassira, Victoria L. Boyd, Noel J. Buckley, Lars Olov Bygren, Claudio M. Caldarera, Gemma Carvill, James W. F. Catto, Sarah Derks, Ewa Dudziec, Jeffrey D. Falk, Jian-Bing Fan, Joseph M. Fernandez, David E. Fisher, Emanuela Fiumana, Tamara B. Franklin, Fei Gao, Arkadiusz Gertych, Emanuele Giordano, David Goldman, Markus Grammel, Carlo Guarnieri, Kevin L. Gunderson, Victoria (Fatemeh) G. Haghighi, Xu Han, Yong-Mahn Han, Howard C. Hang, Aditi Hazra, Laura B.K. Herzing, Norbert Hochstein, Robin Holliday, Dorothee Honsel, Mary A. Jelinek, Guanyu Ji, Yan Jiang, Atsushi Kaneda, Richard A. Katz, Hyemin Kim, Richard Kroon, Tapas K. Kundu, Benoit Labonté, Daeyoup Lee, Konstantin Lepikhov, Andrea Linnemann-Florl, Dirk Loeffert, Dylan Maixner, Isabelle M. Mansuy, Andreas Missel, D. V. Mohankrishna, Joana Carvalho Moreira de Mello, Paolo G. Morselli, Rituparna Mukhopadhyay, Claudio Muscari, Takashi Nagano, Frank Narz, Shuji Ogino, Carlo M. Oranges, Shari Orlanski, Alice Pasini, Ralf Peist, Lygia V. Pereira, Andrey Poleshko, Claire Rougeulle, Thea Rütjes, Ana Sanz, Benjamin G. Schroeder, Gerald Schock, Kornel Schuebel, B. Ruthrotha Selvi, Hogyu Seo, Natalia Shalginskikh, Andrew Sharp, Jun S. Song, Lennart Suckau, Azim Surani, Jian Tajbakhsh, Gustavo Turecki, Céline Vallot, Manon van Engeland, Jörn Walter, Nicholas C. Wong, Mark Wossidlo, Honglong Wu, Yurong Xin, Zhixiang Yan, Yu-Ying Yang, Mingzhi Ye, Kyoko Yokomori, Sephorah Zaman, Weihua Zeng, Gerald Zon
- Edited by Krishnarao Appasani
- Foreword by Azim Surani, University of Cambridge
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- Book:
- Epigenomics
- Published online:
- 05 August 2012
- Print publication:
- 02 August 2012, pp x-xxiv
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- By Alaa A. Abd-Elsayed, Basem Abdelmalak, Kalil G. Abdullah, Maged Argalious, Rafi Avitsian, Maria Bauer, Edward C. Benzel, Dani S. Bidros, William Bingaman, Jay B. Brodsky, David Brown, Patrick M. Callahan, Juan P. Cata, Chakorn Chansakul, Jianguo Cheng, Jeffrey G. Clark, Peter J. Davis, Stacie Deiner, Xiao Di, Karen B. Domino, D. John Doyle, Zeyd Ebrahim, Ehab Farag, Gordon Finlayson, Elizabeth A. M. Frost, Matthew Grosso, David P. Gurd, Rodolfo Hakim, Robert Helfand, Iain H. Kalfas, Rami Karroum, Michael Kelly, Stephen J. Kimatian, Christian Koopman, Ajit A. Krishnaney, Andrea Kurz, Lorri A. Lee, Brian P. Lemkuil, James K. C. Liu, Sara P. Lozano, Daniel Lubelski, Mark Luciano, Ramez Malaty, Mariel R. Manlapaz, Edward M. Manno, Virgilio Matheus, Robert F. McLain, Nagy Mekhail, Doksu Moon, Loran Soliman Mounir, Raghu Mudumbai, Thomas E. Mroz, Dileep R. Nair, Julie Niezgoda, R. Douglas Orr, Piyush M. Patel, Jason E. Pope, Manuel Saavedra, Kenneth J. Saliba, Richard Schlenk, John Seif, John H. Shin, Jeffrey Silverstein, Dmitri Souzdalnitski, Michael Steinmetz, Tunga Suresh, John E. Tetzlaff, Sherif Zaky
- Edited by Ehab Farag
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- Book:
- Anesthesia for Spine Surgery
- Published online:
- 05 June 2012
- Print publication:
- 17 May 2012, pp ix-xii
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