KINDAI UNIVERSITY


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Wataru Imajuku

Profile

FacultyDepartment of Electrical and Communication Engineering / Graduate School of Industory
PositionAssociate Professor
Degree
Commentator Guidehttps://www.kindai.ac.jp/meikan/1495-imajuku-wataru.html
URLhttps://scholar.google.co.jp/citations?user=6UK5BFMAAAAJ&hl=ja
Mail
Last Updated :2019/04/23

Education and Career

Academic & Professional Experience

  •   2016 04 ,  - 現在, Kindai University
  •   2011 07 , Vice President, NTT America Inc/Verio Inc..
  •   2002 12 , Ph. D (The University of Tokyo)
  •   1994 04 , Research Engineer(1994-), Senior Research Engineer(2005-), Supervisor(2013-), Nippon Telegraph and Telephone (NTT) Corp.

Research Activities

Research Areas

  • Electrical and electronic engineering, Communication/Network engineering
  • Informatics, Information network

Published Papers

  • Quantum Noise Analysis of Gain Saturated Periodically Poled Lithium Niobate waveguides, Takuya Takemura, Shun Noguchi, Kunihiko Mori, Mitsunori Fukutoku, and Wataru Imajuku, Proc. of The 13th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-Pacific Rim 2018), W3A.99, Aug. 2018 , Refereed
  • Laser tracking system for aquatic organisms, Yuki Kakushi, Yoshihiko Hibino, Cao Yang, Ryo Amano, Wataru Imajuku, Yasushi Mitsunaga, Shinsuke Torisawa, and Yoshinobu Maeda, Proc. of The 13th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-Pacific Rim 2018), W3A.75, Refereed
  • XPM-induced phase noise mitigation by gain saturated parametric amplifiers, Wataru Imajuku, Kunihiko Mori, and Mitsunori Fukutoku, Proc. of The 13th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-Pacific Rim 2018), W3A.17, Aug. 2018 , Refereed
  • Analytical fiber transfer function with XPM-induced process in N-channel coherent WDM transmission systems, Wataru Imajuku, Kunihiko Mori, and Mitsunori Fukutoku, Proc. of The 13th Pacific Rim Conference on Lasers and Electro-Optics (CLEO-Pacific Rim 2018), W3A.16, Aug. 2018 , Refereed
  • Aero-Aqua Optical Transmission System with Retroreflector and Self-Homodyne Receiver, Wataru Imajuku, Kaoru Kosai, Yuki Kakushi, Yoshihiko Hibino, Ryo Amano, Yasushi Mitsunaga, and Yoshinobu Maeda, Proc. of 2018 Opto-Electronics and Communications Conference (OECC2018), P1-29, Jul. 2018 , Refereed
  • Position Tracking based on AOA and MIMO Combined Technique with Visible Light, Kaoru Kosai, Yuki Hirata, Tsubasa Furuta, Takanori Matsuzaki, and Wataru Imajuku, Proc. of 2018 Opto-Electronics and Communications Conference (OECC2018), P1-16, Jul. 2018 , Refereed
  • Nonlinear Phase Noise Reduction by Gain Saturated Parametric Amplifiers in Coherent Optical Transmission, Wataru Imajuku, Takahiro Nakaishi, Mikiya Kakoi, Kunihiko Mori, and Mitsunori Fukutoku, Proc. of Nonlinear Optics (NLO) 2017, Optical Society of America (OSA), NW4A.14A, Jul. 2017 , Refereed
  • Adaptive and Efficient Multilayer Elastic Optical Network Planning, Imajuku, Wataru, Proc. of 42th European Conference on Optical Communication (ECOC2016), Tu.3.D.1, Sep. 2016 , Refereed
  • Rapid Restoration Sequence of Fiber Links and Communication Paths from Catastrophic Failures, A. Kadohata, T. Tanaka, W. Imajuku, F. Inuzuka, A. Watanabe, IEICE Transaction on Fundamentals of Electronics, Communication and Computers, E99(8), 1510 - 1517, Aug. 2016 , Refereed
  • Multiperiod IP-Over-Elastic Network Reconfiguration With Adaptive Bandwidth Resizing and Modulation, Takafumi Tanaka, Tetsuro Inui, Akihiro Kadohata, Wataru Imajuku, OSA J. OPT. COMMUN. NETW., 8(7), A180 - A190, Jul. 2016 , Refereed
  • A Static traffic grooming algorithm for Optical Networks with Adaptive Modulation, Takafumi Tanaka, Tetsuro Inui, Wataru Imajuku, Proc. of 2016 Opto-Electronics and Communications Conference (OECC 2016), TuA1-3, Jul. 2016 , Refereed
  • Subcarrier Restoration for Survivable Multi-Flow Transponders in Elastic Optical Networks, Takafumi Tanaka and Tetsuro Inui, Wataru Imajuku, Proc. of 21TH ASIA-PACIFIC CONFERENCE ON COMMUNICATIONS (APCC2015), 214 - 217, Oct. 2015 , Refereed
  • vConductor: An Enabler for Achieving Virtual Network Integration as a Service, SHEN WENYU, YOSHIDA MASAHIRO, MINATO KENJI, IMAJUKU WATARU, IEEE Commun Mag, 53(2), 116 - 124, Feb. 2015 , Refereed
  • MORSA: A multi-objective resource scheduling algorithm for NFV infrastructure., Masahiro Yoshida,Wenyu Shen,Taichi Kawabata,Kenji Minato,Wataru Imajuku, Proc. of The 16th Asia-Pacific Network Operations and Management Symposium (APNOMS 2014), Hsinchu, Taiwan, September 17-19, 2014, 2014 , Refereed
  • vConductor: An NFV management solution for realizing end-to-end virtual network services., Wenyu Shen,Masahiro Yoshida,Taichi Kawabata,Kenji Minato,Wataru Imajuku, Proc. of The 16th Asia-Pacific Network Operations and Management Symposium (APNOMS 2014), Hsinchu, Taiwan, September 17-19, 2014, 2014 , Refereed
  • Bandwidth Squeezed Restoration in Spectrum-Sliced Elastic Optical Path Networks (SLICE), SONE Y., WATANABE A., IMAJUKU W., TSUKISHIMA Y., KOZICKI B., TAKARA H., JINNO M., OSA J Opt Commun Netw, 3(1月3日), 223 - 233, Jan. 2011 , Refereed
  • Fast and Flexible Optical Path Accommodation Design Based on Pre-planning and Reconfiguration in Transparent Optical Mesh Networks, Akihiro Kadohata, Atsushi Watanabe, Yoshiaki Sone, Toshikazu Sakano, Wataru Imajuku, and Masahiko Jinno, Proc. of ONDM2010, 6-1, 1 - 6, Feb. 2010 , Refereed
  • Management and Control Scheme Employing Wavelength-Grouped Transmission-Guaranteed Link for Highly-Manageable and Cost-Efficient Transparent Optical Mesh Networks, Yoshiaki Sone, Akihiro Kadohata, Atsushi Watanabe, and Wataru Imajuku, Proc. of 35th European Conference on Optical Communication (ECOC2009), P5.14, 1 - 2, Sep. 2009 , Refereed
  • Highly survivable restoration scheme employing optical bandwidth squeezing in spectrum-sliced elastic optical path (SLICE) network, Yoshiaki Sone Atsushi Watanabe, Wataru Imajuku, Yukio Tsukishima, Bartłomiej Kozicki, Hidehiko Takara, and Masahiko Jinno, Proc. of 2009 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2009), OthO2, 1 - 3, Mar. 2009 , Refereed
  • A Multi-Area MPLS/GMPLS Interoperability Trial over ROADM/OXC Network, IMAJUKU Wataru, OKI Eiji, PAPNEJA Rajiv, MORISHITA Shinichiro, OGAKI Kenichi, MIYAZAWA Masanori, MIYAZAKI Keiji, NAKAZATO Hiroaki, SUGIYAMA Hidetsugu, ALLEN John, HASEGAWA Shinichi, SAKURABA Nobuhiro, NISHIOKA Itaru, SENO Shoichiro, NAKAHIRA Yoshihiro, ISHII Daisuke, OKAMOTO Satoru, VAN UNEN Tara, BLUMHARDT Mark, RAKOTORANTO Hari, PANDIAN Vijay, IEEE Commun Mag, 47(2), 168 - 175, Feb. 2009 , Refereed
  • GMPLS-Based Multiple Failure Recovery Employing Restoration Scheme Escalation in Optical Path Networks, SONE YOSHIAKI, IMAJUKU WATARU, NAGATSU NAOHIDE, JINNO MASAHIKO, IEICE Trans Commun (Inst Electron Inf Commun Eng), E92-B(1), 46 - 58, Jan. 01 2009 , Refereed
  • Empirical Design Technique for Management and GMPLS-Signaling Communication Networks, TANIGUCHI A, TSUKISHIMA Y, IMAJUKU W, SHIMIZU K, HAYASHI R, INOUE I, NOGUCHI K, JINNO M, URUSHIDANI S, Proc. of 14TH ASIA-PACIFIC CONFERENCE ON COMMUNICATIONS (APCC2008), VOLS 1 AND 2, 612 - 616, Oct. 2008 , Refereed
  • Operational Evaluation of ASON/GMPLS Interdomain Capability over a JGN II Network Testbed, TANIGUCHI ATSUSHI, SAMESHIMA YASUNORI, OKAMOTO SHUICHI, OTANI TOMOHIRO, OKANO YUKIFUSA, TSUKISHIMA YUKIO, IMAJUKU WATARU, IEEE Commun Mag, 46(5), 60 - 66, May 2008 , Refereed
  • Service and operation of GMPLS-controlled photonic Internet exchanges, IMAJUKU W, KURAHASHI T, TARUI Y, SHAKE I, MATSUDA K, SHIMAGAMI J, ASABA T, MIYAKE N, TOYAMA K, Proc. of 2008 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2008), VOLS 1-8, 1179 - 1184, Mar. 2008 , Refereed
  • Transpacific Ethernet Transport over GMPLS-based Three Administrative-Domain Photonic Networks, Atsushi Taniguchi, Shuichi Okamoto, John Moore, Yasunori Sameshima, Wataru Imajuku, Tomohiro Otani, Yukihusa Okano, Proc. of 33th European Conference on Optical Communication (ECOC2007), 6.5.5, 1 - 2, Sep. 2007 , Refereed
  • Lambda Sharing Demonstration via Traffic-Driven Lambda-on-Demand, Yukio Tsukishima, Akira Hirano, Naohide Nagatsu, Wataru Imajuku, Proc. of 33th European Conference on Optical Communication (ECOC2007), 6.5.3, 1 - 2, Sep. 2007 , Refereed
  • Theoretical and Experimental Study of Statistical-Decision Method for Link-Capacity Adjustment, YAMAMOTO SHUTO, SHAKE IPPEI, KURAHASHI TOMOHIKO, TARUI YUKIYASU, IMAJUKU WATARU, TSUKISHIMA YUKIO, SASAYAMA KOJI, MORIWAKI OSAMU, FUKUTOKU MITSUNORI, IEEE J Lightwave Technol, 25(9), 2864 - 2873, Sep. 2007 , Refereed
  • Optical Networks Functional Evolution and Control Technologies, SZEGEDI PETER, GAJEWSKI TOMASZ, IMAJUKU WATARU, OKAMOTO SATORU, IEICE Trans Commun (Inst Electron Inf Commun Eng), E90-B(8), 1944 - 1951, Aug. 01 2007 , Refereed
  • GMPLS Based Survivable Photonic Network Architecture, IMAJUKU WATARU, OHARA TAKUYA, SONE YOSHIAKI, SHAKE IPPEI, SAMESHIMA YASUNORI, JINNO MASAHIKO, IEICE Trans Commun (Inst Electron Inf Commun Eng), E90-B(8), 1952 - 1959, Aug. 01 2007 , Refereed
  • GMPLS Interoperability Tests in Kei-han-na Info-Communication Open Laboratory on JGN II Network, OKAMOTO SATORU, IMAJUKU WATARU, OTANI TOMOHIRO, NISHIOKA ITARU, NAGATA AKIRA, NANBA MIKAKO, OTSUKI HIDEKI, SUZUKI MASATOSHI, YAMANAKA NAOAKI, IEICE Trans Commun (Inst Electron Inf Commun Eng), E90-B(8), 1936 - 1943, Aug. 01 2007 , Refereed
  • Challenges and Requirements for ASON/GMPLS Photonic Networks, Wataru Imajuku and Yasunori Sameshima, Proc. of 2007 Opto-Electronics and Communications Conference (OECC2007), 12A1-1, 1 - 2, Jul. 2007 , Refereed
  • The First Optically-Virtual-Concatenated Lambdas Over Multiple Domains in Chicago Metro Area Network Achieved Through Interworking of Network Resource Managers, Yukio Tsukishima, Akira Hirano, Atsushi Taniguchi, Wataru Imajuku, et al., Proc. of 2007 Opto-Electronics and Communications Conference (OECC2007), 12A2-5, 310 - 311, Jul. 2007 , Refereed
  • Theoretical and Experimental Study of Statistical-Decision Method for Link-Capacity Adjustment in Photonic IX, Shuto Yamamoto, Ippei Shake, Tomohiko Kurahashi, Yukiyasu Tarui, Mitsunori Fukutoku, Wataru Imajuku, and Koji Sasayama, Proc. of 2007 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2007), OthQ5, 1 - 3, Mar. 2007 , Refereed
  • Multi-area MPLS/GMPLS Interoperability Trial Over 14-Vendor Packet/TDM/ROADM/OXC Network, Wataru Imajuku, et al., Proc. of 2007 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2007), OthQ2, 1 - 3, Mar. 2007 , Refereed
  • Multiple Failure Recovery of Optical Paths Using GMPLS Based Restoration Scheme Escalation, Yoshiaki Sone, Wataru Imajuku, and Masahiko Jinno, Proc. of 2007 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2007), JthA68, 1 - 3, Mar. 2007 , Refereed
  • Proposal of a Multi-Layered Network Management Methods for GMPLS Networks, OTSUKA Yoshihiro, KIMURA Tatsuyuki, YAGINUMA Hideki, WATANABE Atsushi, IMAJUKU Wataru, The transactions of the Institute of Electronics, Information and Communication Engineers. B, 89(11), 2103 - 2116, Nov. 2006 , Refereed
  • G-lambda: Coordination of a Grid scheduler and lambda path service over GMPLS, TAKEFUSA ATSUKO, HAYASHI MICHIAKI, NAGATSU NAOHIDE, NAKADA HIDEMOTO, KUDOH TOMOHIRO, MIYAMOTO TAKAHIRO, OTANI TOMOHIRO, TANAKA HIDEAKI, SUZUKI MASATOSHI, SAMESHIMA YASUNORI, IMAJUKU WATARU, JINNO MASAHIKO, TAKIGAWA YOSHIHIRO, OKAMOTO SHUICHI, TANAKA YOSHIO, SEKIGUCHI SATOSHI, Future Gener Comput Syst, 22(8), 868 - 875, Oct. 2006 , Refereed
  • JGN II Testbed Demonstration of GMPLS Inter-Carrier Network Control with Actual Operational Consideration, Yasunori Sameshima, Satoru Okamoto, Wataru Imajuku, Tomohiro Otani, and Yukifusa Okano, Proc. of 32th European Conference on Optical Communication (ECOC2006), We. 4.1.5, 1 - 2, Sep. 2006 , Refereed
  • Stable IP-Routing Link Restoration: GUNI Restoration for Data Link Failure Between Routers in a Nationwide Photonic Network, Yukio Tsukishima, Akira Hirano, Naohide Nagatsu, Takuya Ohara, Wataru Imajuku, 他9名, Proc. of 32th European Conference on Optical Communication (ECOC2006), We. 4.1.4, 1 - 2, Sep. 2006 , Refereed
  • Traffic-Driven Distributed LSP Control for MPLS / GMPLS Multi-layer Networks, Atsushi Taniguchi, Yukio Tsukishima, Yasunori Sameshima, Wataru Imajuku, and Masahiko Jinno, Proc. of 2006 Opto-Electronics and Communications Conference (OECC2006), 5E4-6, 1 - 2, Jul. 2006 , Refereed
  • Optical Path Restoration Scheme Escalation Achieving Enhanced Operation and High Survivability in Multiple Failure Scenarios, Yoshiaki Sone, Naohide Nagatsu, Wataru Imajuku, Masahiko Jinno, Yoshihiro Takigawa, Proc. of WTC 2006, NW1.2, 1 - 8, May 2006 , Refereed
  • The first application-driven Lambda-on-demand field trial over a US nationwide network, TSUKISHIMA Y, HIRANO A, NAGATSU N, OHARA T, IMAJUKU W, JINNO M, TAKIGAWA Y, HAGIMOTO K, RENAMBOT L, JEONG B, LEIGH J, DEFANTI T, VERLO A, WINKLER L, Proc. of 2006 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2006), VOLS 1-6, PDP48, 2783 - 2785, Mar. 2006 , Refereed
  • Field trial of signaling interworking of multi-carrier ASON/GMPLS network domains, OKAMOTO S, OTANI T, SONE Y, IMAJUKU W, OGAKI K, MIYAZAWA M, NISHIOKA I, MIYAZAKI K, NAGATA A, SENO S, ISHII D, OKAMOTO S, ARAI N, OTSUKI H, Proc. of 2006 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2006), VOLS 1-6, PDP47, 2780 - 2782, Mar. 2006 , Refereed
  • Router-OXC cooperation for fault recovery employing GMPLS control plane for photonic IX, FUKUTOKU M, KURAHASHI T, TARUI Y, SHAKE I, IMAJUKU W, YAMAMOTO S, SASAYAMA K, Proc. of 2006 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2006), VOLS 1-6, OWQ7, 1014 - 1016, Mar. 2006 , Refereed
  • Design of MPLS/GMPLS multilayer network considering protection and restoration, IMAJUKU W, OHARA T, TAKESHIMA R, UYEMATSU T, SATO K, Proc. of 2006 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2006), VOLS 1-6, OWQ6, 1011 - 1013, Mar. 2006 , Refereed
  • Demonstration of automatic multi-reliability service class LSP provisioning via coordination of GMPLS/OIF-OUNI, OHARA T, IMAJUKU W, FUKUTOKU M, JINNO M, Proc. of 2006 Optical Fiber Communication Conference/National Fiber Optic Engineers Conference (OFC/NFOEC2006), VOLS 1-6, OWQ5, 1008 - 1010, Mar. 2006 , Refereed
  • Highly-Reliable and Fast M:N End-to-End Restoration Scheme for Photonic IP Networks, IMAJUKU WATARU, SONE YOSHIAKI, NAGATSU NAOHIDE, SAHARA AKIO, TAKIGAWA YOSHIHIRO, IEICE Trans Commun (Inst Electron Inf Commun Eng), E88-B(10), 3914 - 3921, Oct. 01 2005 , Refereed
  • Experiments on Optical Link Capacity Adjustment for Photonic IX, Ippei Shake, Mitsunori Fukutoku, Osamu Moriwaki, Tomohiko Kurahashi, Yukiyasu Tarui, Yukio Tsukishima, Wataru Imajuku, Proc. of 31th European Conference on Optical Communication (ECOC2005), 2005(CP502), 217 - 218, Sep. 2005 , Refereed
  • Applications of Optical Parametric Process, Atsushi Takada, Wataru Imajuku, Toshio Morioka, Kazuo Hagimoto, Proc. of OAA2005, WC-1, 1 - 3, Aug. 2005 , Refereed
  • Evaluation of Amount of Equipment on Single-Layer Optical Path Networks Managing Multigranularity Optical Paths, YAMAWAKU JUN, TAKADA ATSUSHI, IMAJUKU WATARU, MORIOKA TOSHIO, IEEE J Lightwave Technol, 23(6), 1971 - 1978, Jun. 2005 , Refereed
  • Nationwide GMPLS field trial using different types (MPLS/TDM/Lambda) of switching capable equipment, Satoru Okamoto, Tomohiro Otani, Wataru Imajuku, D. Shimazaki, Proc. of 2005 Optical Fiber Communication Conference (OFC2005), PDP40, 1 - 3, Mar. 2005 , Refereed
  • Dynamic Multilayer Routing Schemes in GMPLS-Based IP+Optical Networks, OKI E, SHIOMOTO K, SHIMAZAKI D, YAMANAKA N, IMAJUKU W, TAKIGAWA Y, IEEE Commun Mag, 43(1), 108 - 114, Jan. 2005 , Refereed
  • Restoration Path Accommodation Design for Limited Range Wavelength Convertible Photonic Network, Wataru Imajuku, Naohide Nagatsu, and Yoshihiro Takigawa, Proc. of 30th European Conference on Optical Communication (ECOC2004), Tu.1.6.4, 172 - 173, Sep. 2004 , Refereed
  • GMPLS Functionality and Control Plane Architecture for Fault-Tolerant Photonic-IP Network, Wataru Imajuku and Katsuhiro Shimano, Proc. of OECC/COIN-PS 2004, 15B2, 1 - 2, Jul. 2004 , Refereed
  • Performance Evaluation of Dynamic Multi-Layer Routing Schemes in Optical IP Networks, OKI E, SHIOMOTO K, KATAYAMA M, IMAJUKU W, YAMANAKA N, TAKIGAWA Y, IEICE Trans Commun (Inst Electron Inf Commun Eng), E87-B(6), 1577 - 1583, Jun. 2004 , Refereed
  • Distributed Virtual Network Topology Control Mechanism in GMPLS-Based Multiregion Networks, SHIOMOTO K, OKI E, IMAJUKU W, OKAMOTO S, YAMANAKA N, IEEE J Sel Areas Commun, 21(8), 1254 - 1262, Oct. 2003 , Refereed
  • Performance of Dynamic Multi-Layer Routing Schemes in IP+Optical Networks., OKI E, SHIOMOTO K, KATAYAMA M, IMAJUKU W, YAMANAKA N, Proc. of HPSR 2003, S8A-4, 233 - 238, Jun. 2003 , Refereed
  • Scalable shared-risk group management in shared mesh restorable wavelength routed networks, Kohei Shiomoto, Wataru Imajuku, Eiji Oki, Satoru Okamoto, Naoaki Yamanaka, Proc. of HPSR 2003, S6-2, 189 - 194, Jun. 2003 , Refereed
  • Noise Figure of Phase-Sensitive Parametric Amplifier Using a Mach-Zehnder Interferometer With Lossy Kerr Media and Noisy Pump, IMAJUKU W, TAKADA A, IEEE J Quantum Electron, 39(6), 799 - 812, Jun. 2003 , Refereed
  • Performance of Distributed. Controlled Dynamic Wavelength・ Conversion GMPLS Networks, Eiji Oki, Daisaku Shimazaki, Kohei Shiomoto, Nobuaki Matsuura, Wataru Imajuku, Proc. of International Conference on Optical Communication Networks 2002, 355 - 358, Nov. 2002 , Refereed
  • Optical Path Generation Strategy and Network Performance in dynamic multi-layered ip+photonic GMPLS networks, Wataru Imajuku, Naohide Nagatsu, Yoshihiro Takigawa, Eiji Oki, Kohei Shiomoto, and Naoaki Yamanaka, Proc. of 28th European Conference on Optical Communication (ECOC2002), 10.2.4, Sep. 2002 , Refereed
  • Adaptive transparent photonic network control techniques based on photonic-GMPLS-router network, Naoaki Yamanaka, Satoru Okamoto, Kohei Shomoto, Eiji Oki, Wataru Imajuku, Proc. of WTC/ISS 2002, TS-07.3, 1 - 6, Sep. 2002 , Refereed
  • Dynamic multi-layer traffic engineering in GMPLS networks, Kohei Shiomoto, Eiji Oki, Masaru Katayama, Wataru Imajuku, Naoaki Yamanaka, Proc. of WTC/ISS 2002, TS-07.1, 1 - 6, Sep. 2002 , Refereed
  • Performance Evaluation of Optical Label Switching Path Routing Algorithms in Photonic Networks, M. Katayama, E. Oki, K. Shiomoto, N. Yamanaka, W. Imajuku, Proc. of PS2002, PS.ThA2, 217 - 219, Jun. 2002 , Refereed
  • Traffic engineering and signaling technologies in photonic-GMPLS-router networks, YAMANAKA N, OKAMOTO S, SHIOMOTO K, OKI EJ, IMAJUKU W, Proc. of HPSR 2002: WORKSHOP ON HIGH PERFORMANCE SWITCHING AND ROUTING, PROCEEDINGS, 3A-4, 142 - 146, May 2002 , Refereed
  • Heuristic multi-layer optimum topology design scheme based on traffic measurement for IP+ photonic networks, Eiji Oki, Kohei Shiomoto, Satoru Okamoto, Wataru Imajuku, Naoaki Yamanaka, Proc. OFC2002, TuP5, 104 - 105, Mar. 2002 , Refereed
  • GMPLS-Based Photonic Multilayer Router (Hikari Router) Architecture: An Overview of Traffic Engineering and Signaling Technology., SATO K, YAMANAKA N, TAKIGAWA Y, KOGA M, OKAMOTO S, SHIOMOTO K, OKI E, IMAJUKU W, IEEE Commun Mag, 40(3), 96 - 101, Mar. 2002 , Refereed
  • Coherent Optical Amplifier, TAKADA Atsushi, IMAJUKU Wataru, The Review of laser engineering, レーザー研究, 29(9), 599 - 604, Sep. 2001 , Refereed
  • Investigation of number of network elements and costs for virtually grouped wavelength path routing networks, Jun Yamawaku, Wataru Imajuku, Atsushi Takada, Satoru Okamoto, Toshio Morioka, Proc. of OECC2001, TUJ, 194 - 105, Jul. 2001 , Refereed
  • Coherent Optical Amplifiers, Atsushi Takada, Wataru Imajuku, Proc. of 26th European Conference on Optical Communication (ECOC2000), 4.1.2, 87 - 90, Sep. 2000 , Refereed
  • Ultrafast packet ring network employing optical label switching, J.H. Park, A Takada, Wataru Imajuku, Y Yamabayashi, Proc. of 26th European Conference on Optical Communication (ECOC2000), 12A2-3, 90 - 91, Jul. 2000 , Refereed
  • Inline coherent optical amplifier with noise figure lower than 3dB quantum limit., IMAJUKU W, TAKADA A, YAMABAYASHI Y, IET Electron Lett, 36(1), 63 - 64, Jan. 2000 , Refereed
  • Gain Characteristics of Coherent Optical Amplifiers Using a Mach-Zehnder Interferometer with Kerr Media., IMAJUKU W, TAKADA A, IEEE J Quantum Electron, 35(11), 1657 - 1665, Nov. 1999 , Refereed
  • Low-noise amplification under the 3dB noise figure in high-gain phase-sensitive fibre amplifier., IMAJUKU W, TAKADA A, YAMABAYASHI Y, IET Electron Lett, 35(22), 1954 - 1955, Oct. 1999 , Refereed
  • In-line coherent optical amplifier with noise figure under the 3-dB quantum limit, Wataru Imajuku and Atsushi Takada, Proc. of 25th European Conference on Optical Communication (ECOC'99), PDP1-1, 2 - 3, Sep. 1999 , Refereed
  • Theoretical noise figure of phase-sensitive amplifier using Mach-Zender interferometer with lossy Kerr media., IMAJUKU W, TAKADA A, Opt Amplif Appl, ThD2, 347 - 350, Jul. 1999 , Refereed
  • In-Line Optical Phase-Sensitive Amplifier with Pump Light Source Controlled by Optical Phase-Lock Loop., IMAJUKU W, TAKADA A, IEEE J Lightwave Technol, 17(4), 637 - 646, Apr. 1999 , Refereed
  • Pulse Form Reshaping of Chirped Pulse using Optical Phase-Sensitive Amplifier., IMAJUKU W, TAKADA A, Proc. of 1999 Optical Fiber Communication Conference (OFC'99), TUJ4.1-TUJ4.3, Feb. 1999 , Refereed
  • Error-free operation of in-line phase-sensitive amplifier., IMAJUKU W, TAKADA A, IET Electron Lett, 34(17), 1673 - 1674, Aug. 1998 , Refereed
  • Error-free operation of in-line phase-sensitive amplifier, Wataru Imajuku and Atsushi Takada, Proc. of OECC’98, PD1-9, 18 - 19, Jul. 1998 , Refereed
  • Theoretical Analysis of System Limitation for AM-DD/NRZ Optical Transmission Systems Using In-Line Phase-Sensitive Amplifiers., IMAJUKU W, TAKADA A, IEEE J Lightwave Technol, 16(7), 1158 - 1170, Jul. 1998 , Refereed
  • In-line optical phase-sensitive amplifier employing pump laser injection-locked to input signal light., TAKADA A, IMAJUKU W, IET Electron Lett, 34(3), 274 - 276, Feb. 1998 , Refereed
  • In-line phase-sensitive amplifier with optical-PLL-controlled internal pump light source., IMAJUKU W, TAKADA A, IET Electron Lett, 33(25), 2155 - 2156, Dec. 1997 , Refereed
  • Linewidth Narrowing and Optical Phase Control of Mode-Locked Semiconductor Ring Laser Employing Optical Injection Locking., TAKADA A, IMAJUKU W, IEEE Photonic Technol Lett, 9(10), 1328 - 1330, Oct. 1997 , Refereed
  • Optical phase-sensitive amplifier with pump laser phase-locked to input signal light., TAKADA A, IMAJUKU W, Proc. of ECOC'97, Tu2B5(448 Vol.2), 98 - 101, Sep. 1997 , Refereed
  • Optical phase-sensitive amplification using two phase-locked light sources., IMAJUKU W, TAKADA A, IET Electron Lett, 33(16), 1403 - 1404, Jul. 1997 , Refereed
  • Reduction of fiber-nonlinearity-enhanced amplifier noise by means of phase-sensitive amplifiers., IMAJUKU W, TAKADA A, OSA Opt Lett, 22(1), 31 - 33, Jan. 1997 , Refereed
  • The improvement of signal to noise ratio with nonlinear amplification in inline phase-sensitive amplifier systems, Atsushi Takada and Wataru Imajuku, Proc. of OAA’96, SN15, 374 - 376, Jul. 1996 , Refereed
  • Theoretical analysis of lightwave systems using phase-sensitive amplifiers, Wataru Imajuku and Atsushi Takada, Proc. of OECC’96, 17P-18, 246 - 247, Jul. 1996 , Refereed
  • Amplitude noise suppression using a high gain phase sensitive amplifier as a limiting amplifier, TAKADA A, IMAJUKU W, IET Electron Lett, 32(7), 677 - 679, Mar. 1996 , Refereed
  • Amplitude noise suppression by using high-gain phase-sensitive amplifier as limiting amplifier., TAKADA A, IMAJUKU W, Opt Fiber Commun Conf 1996, WA5, 94 - 95, Feb. 1996 , Refereed
  • Theoretical Design of 460 nm ZnCdSSe Laser Diodes., IMAJUKU W, TAKAHASHI M, KOBAYASHI M, YOSHIKAWA A, Jpn J Appl Phys Part 1, 34(4A), 1861 - 1866, Apr. 1995 , Refereed

Books etc

  • IETF RFC 7581: Routing and Wavelength Assignment Information Encoding for Wavelength Switched Optical Networks, G. Bernstein, Y. Lee, D. Li, W. Imajuku, and J. Han, Joint Work, IETF RFC 7581: Routing and Wavelength Assignment Information Encoding for Wavelength Switched Optical Networks, InternetEngineering Task Force,   2015 06
  • IETF RFC 7579: General Network Element Constraint Encoding for GMPLS-Controlled Networks, G. Bernstein, Y. Lee, D. Li, W. Imajuku, and J. Han, Joint Work, InternetEngineering Task Force,   2015 06
  • IETF RFC 7446: Routing and Wavelength Assignment Information Model for Wavelength Switched Optical Networks, Y. Lee, G. Bernstein, D. Li, and W. Imajuku, Joint Work, InternetEngineering Task Force,   2015 02
  • IETF RFC 6163: Framework for GMPLS and Path Computation Element (PCE) Control of Wavelength Switched Optical Networks (WSONs), Y. Lee, G. Bernstein and W. Imajuku, Joint Work, InternetEngineering Task Force,   2011 04
  • 1997 Tops Optical Amplifiers and Their Applications (OSA Trends in Optics and Photonics), Imajuku, Wataru, Contributor,   1997 07 , 1-55752-505-6

Conference Activities & Talks

  • Challenges and Solution for ICT deployment in rural area, Imajuku, Wataru, IEEE International Conference on ICT for Rural Development,   2018 10 17 , 招待有り
  • Impact of Highly Adaptive Elastic Optical Paths on Dynamic Multi-layer Network Planning, Takafumi Tanaka, Tetsuro Inui, Akihiro Kadohata, and Wataru Imajuku, imajuku@fuk.kindai.ac.jp,   2016 06 16
  • NFV and Transport SDN Orchestration: Possible Use Cases and Issues Toward Commercialization, Imajuku, Wataru, OFC 2015,   2015 03 23 , 招待有り
  • Management and Control Architecture of Intelligent Transparent Optical Networks, Imajuku, Wataru, OFC 2009 NMD3,   2009 03 23 , 招待有り
  • Multi-area MPLS/GMPLS Interoperability Trial Over 14-Vendor Packet/TDM/ROADM/OXC Network, Imajuku, Wataru, OFC 2008,   2008 02 25 , 招待有り
  • Challenges and Requirements for ASON/GMPLS Photonic Networks, Imajuku, Wataru, OECC2007 12A1-1,   2007 07 12 , 招待有り
  • Photonic IP Network Technology - The State-of-The-Art and Challenging Issues, Imajuku, Wataru, 2004 Japan-America Frontiers of Engineering Symposium,   2004 11 05 , 招待有り
  • GMPLS Functionality and Control Plane Architecture for Fault-Tolerant Photonic-IP Network, Imajuku, Wataru, OECC/COIN-PS 2004 15B2,   2004 07 15 , 招待有り
  • Coherent optical amplifier using degenerative parametric process in silica fiber, Imajuku, Wataru, 2001 International Symposium on Signals, Systems TH3-B4,   2001 07 26 , 招待有り
  • Application Free Space Optical Transmission Technologies to High Definition Positioning Systems, K. Kosai, Y. Hirata, T. Furuta, and W. Imajuku,   2018 03
  • Free Space Optical Transmission System Design for Transferring BioLog of Marine Organism, W. Imajuku, K, Kosai, Y. Mitsunaga, Y. Hibino, Y. Kakushi, and Y. Maeda,   2018 03
  • Nonlinear Phase Noise Reduction by Gain Saturated Parametric Amplifiers, W. Imajuku, S. Noguchi, T. Takemura, K. Mori, and M. Fukutoku,   2018 03
  • Noise Characteristic Analysis of Gain Saturated PPLN-based Optical Amplifiers, T. Takemura, S. Noguchi, and W. Imajuku,   2018 03
  • BT-2-2 Expectations and issues of Network Functions Virtualization Technology, Imajuku Wataru, Proceedings of the IEICE General Conference,   2014 03 04 , 招待有り
  • B-7-33 An Application of Multi-objective Genetic Algorithm for NFI Resource Optimization, Yoshida Masahiro, Shen Wenyu, Minato Kenji, Imajuku Wataru, Proceedings of the Society Conference of IEICE,   2014 09 09
  • B-7-13 A Study of a Network-Aware Infrastructure Management Module for NFV, Yoshida Masahiro, Shen Wenyu, Kawabata Taichi, Minato Kenji, Imajuku Wataru, Proceedings of the IEICE General Conference,   2014 03 04
  • B-7-12 A Study of a Virtualized Service Orchestrator, Shen Wenyu, Yoshida Masahiro, Kawabata Taichi, Minato Kenji, Imajuku Wataru, Proceedings of the IEICE General Conference,   2014 03 04
  • BP-4-1 Main issues for constructing 100Gbps-base Photonic Transport Networks, Imajuku Wataru, Urahata Tomoyuki, Proceedings of the Society Conference of IEICE,   2010 08 31 , 招待有り
  • B-14-2 End-to-End Management Architecture for Ethernet Line with Ethernet OAM, Okada Kouichi, Harada Makoto, Nagao Norihiko, Usui Tadashi, Imajuku Wataru, Proceedings of the Society Conference of IEICE,   2010 08 31
  • B-12-34 Management and Control Scheme Employing Wavelength-Grouped Transmission-Guaranteed Link for Highly-Manageable and Cost-Efficient Transparent Optical Mesh Networks, Sone Yoshiaki, Kadohata Akihiro, Watanabe Atsushi, Imajuku Wataru, Jinno Masahiko, Proceedings of the IEICE General Conference,   2010 03 02
  • B-12-1 Bandwidth Squeezing Restoration in Bandwidth Variable Optical Path Networks, Sone Yoshiaki, Watanabe Atsushi, Imajuku Wataru, Tsukishima Yukio, Kozicki Bartlomiej, Takara Hidehiko, Jinno Masahiko, Proceedings of the Society Conference of IEICE,   2009 09 01
  • B-7-29 Comparison of Optical Path Accommodation Schemes in Transparent Optical Network, Kadohata Akihiro, Watanabe Atsushi, Sone Yoshiaki, Imajuku Wataru, Jinno Masahiko, Proceedings of the IEICE General Conference,   2009 03 04
  • BK-1-11 Ethernet Transport over GMPLS-based Transpacific Three Administrative Domain Photonic Networks, Taniguchi Atsushi, Okamoto Shuichi, Moore John H., Sameshima Yasunori, Imajuku Atsushi, Otani Tomohiro, Okano Yukifusa, Proceedings of the IEICE General Conference,   2008 03 05
  • B-12-14 The Optical-Virtual-Concatenation of Parallel Lambdas Over Multiple Domains, Tsukishima Yukio, Hirano Akira, Taniguchi Atsushi, Imajyuku Wataru, Jinno Masahiko, Proceedings of the Society Conference of IEICE,   2007 08 29
  • B-12-13 A proposal of the scheme enhancing fairness in GMPLS path restorations using the scheduling of resource allocation, Sone Yoshiaki, Yamamoto Shuto, Imajuku Wataru, Jinno Masahiko, Proceedings of the Society Conference of IEICE,   2007 08 29
  • B-12-25 A demonstration of the multiple-failure recovery using GMPLS-based restoration scheme escalation, Sone Yoshiaki, Imajuku Wataru, Jinno Masahiko, Proceedings of the IEICE General Conference,   2007 03 07
  • B-12-20 Field Trial of Cut-Through Path Control Based on MPLS/GMPLS Interworking over JGN II Testbed, Sameshima Yasunori, Taniguchi Atsushi, Imajuku Wataru, Tsukishima Yukio, Ohara Takuya, Okano Yukifusa, Proceedings of the Society Conference of IEICE,   2006 09 07
  • B-12-16 A study of optical path resource allocation strategies for multiple failures, Sone Yoshiaki, Imajuku Wataru, Jinno Masahiko, Proceedings of the Society Conference of IEICE,   2006 09 07
  • B-12-17 Experiment on link capacity adjustment using TDM/optical path cooperation for photonic IX, Yamamoto Shuto, Kurahashi Tomohiko, Tarui Yukiyasu, Fukutoku Mitsunori, Shake Ippei, Imajuku Wataru, Sasayama Kouji, Proceedings of the IEICE General Conference,   2006 03 08
  • B-12-6 Demonstration of Automatic Multi-Reliability Service Class LSP Provisioning via Coordination of GMPLS/OIF-OUNI, Ohara Takuya, Imajuku Wataru, Fukutoku Mitsunori, Jinno Masahiko, Proceedings of the IEICE General Conference,   2006 03 08
  • B-12-16 Experiment on fault recovery using multi-layer cooperation for photonic IX, Shake Ippei, Kurahashi Tomohiko, Tarui Yukiyasu, Fukutoku Mitsunori, Yamamoto Shuto, Imajuku Wataru, Sasayama Kouji, Proceedings of the IEICE General Conference,   2006 03 08
  • B-12-15 Router-OXC Cooperation for Fault Recovery Employing GMPLS Control Plane for Photonic IX, Fukutoku Mitsunori, Kurahashi Tomohiko, Tarui Yukiyasu, Shake Ippei, Imajuku Wataru, Yamamoto Shuto, Sasayama Kouji, Proceedings of the IEICE General Conference,   2006 03 08
  • B-12-17 Optical path routing strategies applicable to multiple link failures, Sone Yoshiaki, Nagatsu Naohide, Imajuku Wataru, Takigawa Yoshihiro, Proceedings of the Society Conference of IEICE,   2005 09 07
  • SB-2-3 General Switch Management Protocol for Photonic Network, Shimano Katsuhiro, Imajuku Wataru, Sahara Akio, Tsukishima Yukio, Watanabe Atsushi, Koga Masafumi, Takigawa Yoshihiro, Proceedings of the IEICE General Conference,   2004 03 08
  • B-10-89 Network Design Algorithms for Photonic IP Networks Considering Optical Path Restoration, TAKESHIMA Ryota, UYEMATSU Tomohiko, IMAJUKU Wataru, SATO Ken-ichi, Proceedings of the IEICE General Conference,   2004 03 08
  • B-10-87 A study of RSVP-TE based M:N Restoration Protocol, IMAJUKU Wataru, SHIMANO Katsuhiro, TAKIGAWA Yoshihiro, Proceedings of the IEICE General Conference,   2004 03 08
  • A study of GMPLS control-plane architecture and the development of Link Management Protocol, Imajuku W., Shimano K., Takigawa Y., Proceedings of the IEICE General Conference,   2003 03 03
  • Scaleable SRG-based restoration method in photonic networks, Shiomoto Kohei, Imajuku Wataru, Oki Eiji, Okamoto Satoru, Yamanaka Naoaki, Takigawa Yoshihiro, Proceedings of the IEICE General Conference,   2003 03 03
  • Proposal of parametric wavelength conversion circuit for the grouped wavelength path routing, Imajuku Wataru, Yamawaku Jun, Takada Atsushi, Morioka Toshio, Proceedings of the IEICE General Conference,   2001 03 07
  • Element number evaluation on the grouped wavelength path routing network, Yamawaku Jun, Imajuku Wataru, Takada Atsushi, Okamoto Satoru, Proceedings of the IEICE General Conference,   2001 03 07
  • Low noise coherent optical amplification under the standard quantum limit, Imajuku Wataru, Takada Atsushi, Yamabayashi Y., Proceedings of the IEICE General Conference,   2000 03 07
  • Ultra-fast Optical Packet Add Drop Multiplexer Ring Network, Park Jin Hun, TakadA Atsushi, Imajuku Wataru, Yamabayashi Yoshiaki, Proceedings of the IEICE General Conference,   2000 03 07
  • B-10-169 Coherent Optical Frequency Conversion using Four-Wave Mixing with Phase-Locked Pump Light, Takada Atsushi, Imajuku Wataru, Proceedings of the IEICE General Conference,   1999 03 08
    Summary:光周波数偏移幅がマイクロ波発信器の精度で、かつ信号光の光位相を保持したままでの光波長変換技術は将来の光位相を利用する光リンク/ネットワークの構築上重要である。今回、信号光の有する光位相を維持したコヒーレントな波長変換を目指して、入射する信号光にオフセット光位相同期したレーザ光で励起されたファイバ四光波混合実験を行った。その結果、入射光の線幅が保存された波長変換に成功したので報告する。
  • B-10-70 Ultra-High-Speed Pulse-Form Reshaping by Optical Phase-Sensitive Amplifier, Imajuku Wataru, Takada Atsushi, Proceedings of the IEICE General Conference,   1999 03 08
    Summary:位相感応型光増幅器(PSA)は、光非線形媒質中の縮退パラメトリック(縮退四光波混合)過程により、光位相に依存した光信号利得を実現する。そのためPSAは、伝送ファイバの分散及び非線形効果に起因したチャープでパルス幅の広がった信号光パルスを波形整形できることが理論的に指摘されている。しかしながら、励起光-信号光間の光位相同期が困難であり、実験的な検証はこれまでされていなかった。本稿では励起光-信号光間の光位相同期を光PLLで実現し、PSAの光位相依存利得特性を用いた信号光波形整形動作を実験的に確認したので報告する。
  • Optical Phase-locking of Actively Mode-Locked Ring Laser Diode by Optical Pulse Injection, A. Takada and W. Imajuku,   1998 03 29
  • Stabilization of An Optical phase-Sensitive Amplifier using Optical Injection and Optical Phase-lock loop, Imajuku Wataru, Takada Atsushi, Proceedings of the IEICE General Conference,   1998 03 06
  • Optical Phase-Sensitive Amplifier using Injection Locked Pump Laser, Takada Atsushi, Imajuku Wataru, Proceedings of the Society Conference of IEICE,   1997 08 13
    Summary:位相感応型光増幅器(PSA:Phase Sensitive Amplifier)は、無雑音で変調不安定性抑圧機能等があるため中継増幅器としての適用が期待できる。PSAを中継器として適用するためには、信号光に位相同期した励起光を用いることが必要であるが従来実現していなかった。光位相同期の達成には光位相同期ループを用いる方法と光注入同期法によるものがあるが、今回光注入同期により信号光に光位相同期した励起光を用いたPSA実験に初めて成功したので報告する。
  • Optical phase-sensitive amplification using optical phase-locked light source with PLL, Imajuku Wataru, Takada Atsushi, Proceedings of the Society Conference of IEICE,   1997 08 13
    Summary:位相感応型光増幅器(PSA)は、標準量子限界(NF=3dB)以下の低雑音性、変調不安定性の抑圧効果を有するため、中継器としての適用が期待できる。このPSAでは、励起光と信号光の光位相同期が必要であるが、従来実現されていなかった。光位相同期には光注入同期法と光位相同期ループ(光PLL)を用いる方法があるが、今回初めて光PLLにより信号光と励起光の光位相を同期させ、安定に光位相依存光増幅動作を実現したので報告する。
  • Optical phase locking of mode-locked semiconductor ring laser by optical PLL and injection locking, TAKADA A., IMAJUKU W., KATAGIRI Y., NISHI S., Annual meeting, of the Laser Society of Japan digest of technical papers,   1997 01
  • Maximum Regenerative Transmission Distance of PSA In-Line Optical Transmission System, Imajuku Wataru, Takada Atsusi, Proceedings of the IEICE General Conference,   1996 03 11
    Summary:入射光の位相に依存した利得を与える位相感応光増幅器(PSA :Phase Sensitive Amplifier)は、無雑音[1]でかつチャープパルスの波形整形機能がある[2]ため中継増幅器としての適用が期待できる。今回、PSA多中継伝送系の最大再生中継間隔について理論的に検討し、初めて明らかにしたので報告する。
  • Phase Sensitive Amplifier using Optical Kerr Effect, Takada Atsushi, Imajuku Wataru, Proceedings of the IEICE General Conference,   1996 03 11
    Summary:入射光の位相に依存した利得を与える位相感応光増幅器(PSA:Phase Sensitive Amplifier)は、無雑音でかつチャープパルスの波形整形機能があるため中継増幅器としての適用が期待できる。今回、光カー効果を用いたPSAの基本特性について、理論的、実験的に検討したので報告する。
  • The effect of the strain in the active layer on the device performance of the ZnSe based QW laser diode, W. Imajuku, H. Kaji, M. Kobayashi, and A. Yoshikawa,   1994 03 30
  • 30p-HB-6 ZnCdSSe laser diode strucure to realize lazing of 460nm at RT and the analysis of the threshold current density, W. Imajuku, M. Kobayashi, and Y. Akehiko,   1993 09 30
  • Theoretical approach to ZnCdSe/ZnSSe Laser Diodes, W. Imajuku, M. Takahashi, M. Kobayashi, adn A. Yoshikawa,   1993 04 01

Misc

  • Eigenvalue equation of optical transmission fiber considering cross-phase modulation (XPM) induced instability, Imajuku, Wataru, REPORTS of Faculty of Humanity-Oriented Science and Engineering KINDAI UNIVERSITY, 26, 1, 11, 20,   2017 07
  • Standardization of IP and Optical Networking Technologies, INOUE ICHIRO, OKI EIJI, TAKEDA TOMONORI, SHIOMOTO KOHEI, IMAJUKU WATARU, NTT Tech Rev (Web), 6, 4, WEB ONLY,   2008 04 , Refereed, http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902226517876194
  • Coherent optical amplifier, IMAJUKU Wataru, TAKADA Atsushi, OYOBUTURI, 69, 11, 1320, 1324,   2000 , Refereed, 招待有り, 10.11470/oubutsu1932.69.1320, http://ci.nii.ac.jp/naid/130003594081
    Summary:コヒーレント光増幅器は,コヒーレント光検波技術と光パラメトリック増幅技術を併用することで,光位相に依存したパワー利得を実現する線形光増幅器である.この特徴的な動作により,既存のレーザー光増幅器,ラマン光増幅器などの限界とされる標準量子限界(雑音指数3dB)以下の低雑音光増幅が原理的に可能とされる.また,光周波数チャーピングにより波形がひずんだ超短パルスの波形整形動作も実現可能である.本稿では,このコヒーレント光増幅器の原理と,最近の研究動向について紹介する.
  • Multi-layer Path Configuration Management System in Cooperation with GMPLS, YAMADA Kazuhisa, SONE Yoshiaki, IMAJUKU Wataru, JINNO Masahiko, IEICE technical report. Information and communication management, 108, 123, 13, 17,   2008 07 03 , http://ci.nii.ac.jp/naid/110006990053
    Summary:We propose the multi-layer path configuration management system that constructs and manages the accommodation relation of path between layers of multi-layer network in cooperation with GMPLS automatically. We describe about the path management model of GMPLS to construct the accommodation relation of multi-layer path. Moreover, associating the passing management data constructed with GMPLS and the passing management data of a high-ranking operation system is clarified. Specific speed-up of the grasp related to the accommodation of multi-layer path and the extent of the impact of the breakdown occurrence can be expected by using this system.
  • Proposal of Optical Path Re-allocation Scheme in Transparent Optical Networks, KADOHATA Akihiro, WATANABE Atsushi, SONE Yoshiaki, SAKANO Toshikazu, IMAJUKU Wataru, JINNO Masahiko, IEICE technical report, 109, 172, 47, 52,   2009 08 11 , http://ci.nii.ac.jp/naid/110007356244
    Summary:In transparent optical networks, the optical path accommodation design must consider the continuous wavelength allocation constraint from source to destination and the transmission impairment constraint. The optical path accommodation schemes considering those two constraints are classified into the pre-planning scheme and the post-planning scheme. In this paper, we propose the re-allocation scheme in the pre-planning scheme in order to minimize the expansion of the facility cost even in the case of demand fluctuation and clarify the effectiveness of the proposed scheme through quantitative evaluation.
  • Operational Evaluation of ASON/GMPLS Inter-domain Capability over JGN II Network Testbed, TANIGUCHI Atsushi, SAMESHIMA Yasunori, OKAMOTO Shuichi, OTANI Tomohiro, TSUKISHIMA Yukio, IMAJUKU Wataru, Technical report of IEICE. OCS, 108, 83, 15, 20,   2008 06 05 , http://ci.nii.ac.jp/naid/110006951332
    Summary:Traffic engineering in backbone networks is an important issue in supporting an appropriate Quality of Service (QoS) level in order to accommodate efficiently various types of traffic flows. Automatically switched optical networks (ASON) and Generalized Multi-Protocol Label Switching (GMPLS) control planes are promising functionalities to achieve the sophisticated mechanism of inter-domain traffic engineering. In this article, we address dynamic operational scenarios to control IP traffic flows using the ASON/GMPLS control plane. This includes cut through IP/MPLS routers and the rerouting of failed links through the tunnel of Optical Label Switched Paths (OLSPs). This paper presents an operational evaluation of traffic engineering using state-of-the-art optical switching and control plane technologies. More specifically, we present QoS recovery for protecting high priority traffic using policy controllers, and fault recovery of inter-domain LSPs over the JGN II network testbed.
  • An Experiment of Co-allocating Computing and Lambda Path Resources on the Grid, TAKEFUSA ATSUKO, HAYASHI MICHIAKI, NAGATSU NAOHIDE, NAKADA HIDEMOTO, KUDOH TOMOHIRO, MIYAMOTO TAKAHIRO, OTANI TOMOHIRO, TANAKA HIDEAKI, SAMESHIMA YASUNORI, IMAJUKU WATARU, JINNO MASAHIKO, TAKIGAWA YOSHIHIRO, OKAMOTO SHUICHI, TANAKA YOSHIO, SEKIGUCHI SATOSHI, IPSJ SIG Notes, 2006, 20, 121, 126,   2006 02 27 , http://ci.nii.ac.jp/naid/110004710271
    Summary:AIST, KDDI R&D Laboratories and NTT are promoting collaborative project G-lambda to establish a standard Web services interface between Grid and network resources. At iGrid2005, we conducted a experiment in cooperation with NICT, where our Grid scheduling system coallocated computing and network resources with advance reservation through the interface. In this report, our co-allocation system model, the Web services interface (GNS-WSI) between GRS (Grid Resource Scheduler) and NRM (Network Resource Management System), overview of GRS which AIST has developed and NRM which KDDI R&D laboratories developed, and overview of the experiment are described.
  • Resilient photonic networking considering multiple failures, SONE Yoshiaki, NAGATSU Naohide, IMAJUKU Wataru, TAKIGAWA Yoshihiro, 電子情報通信学会技術研究報告. PN, フォトニックネットワーク, 105, 236, 65, 70,   2005 08 12 , http://ci.nii.ac.jp/naid/110003223763
    Summary:Photonic networks (PNW's) need to be robust against failures as very high-speed optical paths (OP's) like 2.5Gbps, 10Gbps, and so forth, are operated therein. In particular, failure recovery scheme against multiple failures is essential to establish highly reliable PNW. This paper intends to open up an opportunity for the reliability enhancement of PNW, particularly, against multiple failures, and proposes a novel multiple-failure recovery scheme where both pre-assigned and dynamic restorations gracefully co-functions. We begin with network dimensioning using the OP accommodation design tool we developed to determine the effectiveness of the proposed recovery scheme in terms of the survivability. We then implemented a couple of policies as to how pre-assigned and dynamic restorations are co-related into the OP accommodation design tool to find out the criterion determining the order of setting up new OP.
  • The Standard Switch Management Protocol for Enhancing Photonic Network Control Functionality, IMAJUKU Wataru, SHIMANO Katsuhiro, SAHARA Akio, TSUKISHIMA Yukio, WATANABE Atsushi, KOGA Masafumi, TAKIGAWA Yoshihiro, 電子情報通信学会技術研究報告. PN, フォトニックネットワーク, 104, 84, 69, 74,   2004 05 20 , http://ci.nii.ac.jp/naid/110003223737
    Summary:Label-switching nodes with Generalized Multi-Protocol Label Switching (GMPLS) controller have been convened much attention as a promising way to realize next-generation IP back-bone network, which emphasizes the importance of the reusability of the GMPLS controller, bunch of huge volume softwares, to reduce development, deployment and maintenance costs of the nodes. This paper focuses on a generic specification of a switch management and control interface as a mean of reducing these costs. This paper studies General Switch Management Protocol (GSMP) standardized in Internet Engineering Task Force (IETF) for further generalization and adaptation to photonic network. Then, this paper reports the result of performance evaluation of phonic MPLS routers with the GSMP studied.
  • Network Design Algorithms for Multi-Layer Photonic IP Networks Considering Optical Path Restoration, TAKESHIMA Ryota, UYEMATSU Tomohiko, IMAJUKU Wataru, SATO Ken-ichi, 電子情報通信学会技術研究報告. PN, フォトニックネットワーク, 104, 1, 5, 10,   2004 04 06 , http://ci.nii.ac.jp/naid/110003223643
    Summary:Photonic IP networks that integrate wavelength routing and layer 3 cut-through capability are promising candidate to transport large capacity IP traffic effectively. This paper proposes multi-layered optimal accommodation design algorithms that accommodates both LSPs (Label Switched Paths) and OLSPs (Optical LSPs) considering IP traffic for multi-layered photonic IP networks with LSP and OLSP layer. In order to enhance the reliability of networks, we employ optical path restoration scheme considering route independency of working and back-up paths, and evaluate the number of fibers which is needed whole Photonic IP networks. Simultaneously, we clarified advantages and disadvantages considering route independency.
  • The Standard Switch Management Protocol for Enhancing Photonic Network Control Functionality, IMAJUKU Wataru, SHIMANO Katsuhiro, SAHARA Akio, TSUKISHIMA Yukio, WATANABE Atsushi, KOGA Masafumi, TAKIGAWA Yoshihiro, IEICE technical report. Communication systems, 104, 80, 69, 74,   2004 05 20 , http://ci.nii.ac.jp/naid/110003282119
    Summary:Label-switching nodes with Generalized Multi-Protocol Label Switching (GMPLS) controller have been convened much attention as a promising way to realize next-generation IP back-bone network, which emphasizes the importance of the reusability of the GMPLS controller, bunch of huge volume softwares, to reduce development, deployment and maintenance costs of the nodes. This paper focuses on a generic specification of a switch management and control interface as a mean of reducing these costs. This paper studies General Switch Management Protocol (GSMP) standardized in Internet Engineering Task Force (IETF) for further generalization and adaptation to photonic network. Then, this paper reports the result of performance evaluation of phonic MPLS routers with the GSMP studied.
  • Multi-layer dynamic routine in GMPLS networks, OKI Eiji, SHIOMOTO Kohei, KATAYAMA Masaru, IMAJUKU Wataru, YAMANAKA Naoaki, TAKIGAWA Yoshihiro, Technical report of IEICE. OCS, 103, 69, 7, 12,   2003 05 15 , http://ci.nii.ac.jp/naid/110003285291
    Summary:This paper presents two dynamic multi-layer routing policies for optical IP Networks. Both policies first try to allocate a newly requested electrical path to an existing optical path that directly connects the source and destination nodes. If such a path is not available, the two policies employ different procedures. Policy 1, which has been published already, tries to find available existing optical paths with two or more hops that connect the source and destination nodes. Policy 2, which is proposed in this paper, tries to establish a new one-hop optical path between source and destination nodes. The performances of the two routing policies are evaluated. Simulation results suggest that policy 2 outperforms policy 1 if p is large, where p is the number of packet-switching-capable ports p; the reverse is true only if p is small. We observe that p is the key factor in choosing the most appropriate routing policy.
  • Multi-layer dynamic routing in GMPLS networks, OKI E, SHIOMOTO K, KATAYAMA M, IMAJUKU W, YAMANAKA N, TAKIGAWA Y, 電子情報通信学会技術研究報告, 103, 69(OCS2003 8-15), 7, 12,   2003 05 22 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902228184009520
  • Scalable SRG-based restoration method in wavelength networks., SHIOMOTO K, IMAJUKU W, OKI E, 電子情報通信学会技術研究報告, 102, 649(OCS2002 109-118), 21, 24,   2003 02 18 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902250509985624
  • Scalable SRG-based restoration method in wavelength networks, SHIOMOTO Kohei, IMAJUKU Wataru, OKI Eiji, OKAMOTO Satoru, Yamanaka Naoaki, Takigawa Yoshihiro, IEICE technical report, 102, 647, 21, 24,   2003 02 11 , http://ci.nii.ac.jp/naid/110003172391
    Summary:This paper proposes a scaleable SRG-based restoration method in shared mesh wavelength-routed networks. We introduce a backup-SRG concept to identify which SRG is backed up by individual links. We developed an admission control method for backup path using the backup-SRG concept to achieve 100% recovery performance. The proposed method is extended to support networks with a large number of SRGs by introducing hierarchical SRG assignment technique.
  • Dynamic Optical Path Generation Strategy in IP+Photonic Peer-Model Network, Imajuku Wataru, Oki Eiji, Shiomoto Kohei, Yamanaka Naoaki, Nagatsu Naohide, Takigawa Yoshihiro, IEICE technical report. Communication systems, 102, 102, 35, 40,   2002 05 24 , http://ci.nii.ac.jp/naid/110003281785
    Summary:This paper discusses the requirements for extending routing protocols to realize IP+Photonic multi-layered networking under the Generalized Multi-Protocol Label Switching (GMPLS) controller. This paper also proposes dynamic optical-path generation algorithms and evaluates their impact on the performance of the IP+Photonic multi-layered GMPLS network comprising label-switching routers with integrated packet and lambda switching capability. Then, the optical label-switched path (O-LSP) Creation First (OCF) strategy is elucidated, which provides excellent throughput in high network capacity.
  • Dynamic Optical Path Generation Strategy in IP+Photonic Peer-Model Network., IMAJUKU W, OKI E, SHIOMOTO K, YAMANAKA N, NAGATSU N, TAKIGAWA Y, 電子情報通信学会技術研究報告, 102, 104(OCS2002 19-30), 35, 40,   2002 05 31 , http://jglobal.jst.go.jp/detail.php?from=API&JGLOBAL_ID=200902155813989048
  • Evaluation for the amount of NW elements in grouped-wavelength-routing NWs and lump wavelength converter, Yamawaku Jun, Takada Atsushi, Imajuku Wataru, Nagatsu Naohide, Morioka Toshio, Technical report of IEICE. OCS, 102, 104, 11, 16,   2002 05 24 , http://ci.nii.ac.jp/naid/110003286151
    Summary:So far, we have evaluated that a grouped-wavelength-path, which is a bundle of wavelength continuous paths between a node pair, could suppress the node scale, securing node throughput with a simple node configuration. This method, however, requires more bandwidth than conventional wavelength routing because of the vacant path in the grouped-wavelength-path. To accomplish the node scale suppression, efficient resource utilization, and simple configuration, we propose wavelength / grouped-wavelength setting node which handle these paths in each format, and compare it with conventional wavelength path routing node in terms of the amount of NW elements required for traffic load. Furthermore, we evaluated cross talk in lump wavelength converter. Wavelength converter is the key device for the grouped-wavelength routing to attain the node scale suppression. Crosstalk of Optical fiber (FWM) and Periodically Poled LiNbO_3(PPLN:χ_2Cascading) is evaluated theoretically as an example of one lump wavelength converter.
  • Dynamic Optical Path Generation Strategy in IP+Photonic Peer-Model Network, Imajuku Wataru, Oki Eiji, Shiomoto Kohei, Yamanaka Naoaki, Nagatsu Naohide, Takigawa Yoshihiro, Technical report of IEICE. OCS, 102, 104, 35, 40,   2002 05 24 , http://ci.nii.ac.jp/naid/110003286155
    Summary:This paper discusses the requirements for extending routing protocols to realize IP+Photonic multi-layered networking under the Generalized Multi-Protocol Label Switching (GMPLS) controller. This paper also proposes dynamic optical-path generation algorithms and evaluates their impact on the performance of the IP+Photonic multi-layered GMPLS network comprising label-switching routers with integrated packet and lambda switching capability. Then, the optical label-switched path (O-LSP) Creation First (OCF) strategy is elucidated, which provides excellent throughput in high network capacity.
  • Performance Evaluation of Distributed-Controlled Dynamic Wavelength-Conversion GMPLS Networks, OKI Eiji, SHIMAZAKI Daisaku, SHIOMOTO Kohei, MATSUURA Nobuaki, IMAJUKU Wataru, YAMANAKA Naoaki, Technical report of IEICE. OCS, 102, 40, 5, 10,   2002 04 26 , http://ci.nii.ac.jp/naid/110004024799
    Summary:This paper presents the performance of distributed-controlled dynamic wavelength-conversion (DDWC) optical networks based on our simple route and wavelength assignment (RWA) policy. A source node first chooses an optical-path route by using aggregated optical link-state information, then sends a signaling message on the selected route, after which wavelength assignment is performed. If wavelength conversion is needed at a transit node, the wavelength is adaptively converted by using trunk-type wavelength converters. The advertised information overhead incurred by the routing protocol and the cost processing incurred in solving the complicated RWA problem at the source node are reduced. We show via simulations that the performance of the DDWC network with our simple RWA policy emulates that of the WC network with small number of trunk-type wavelength converters.
  • Dynamic multi-layer traffic engineering in MPLambdaS networks : The Format of Technical Report (Subtitle), Shiomoto Kohei, Oki Eiji, Katayama Masaru, Imajuku Wataru, Yamanaka Naoaki, Technical report of IEICE. PS, 102, 1, 55, 60,   2002 04 03 , http://ci.nii.ac.jp/naid/110004024866
    Summary:This paper proposes a simple dynamic traffic engineering method in hierarchical GMPLS networks. Virtual topologies in optical and electrical layers are re-configured in a graceful way responding the traffic demand change. The electrical layer re-routing is done first with make-before-break technique assuming the anticipated virtual optical layer topology before the optical layer rerouting is done. The proposed method satisfies the six goals, which we raised: (1) simple, (2) fast, (3) efficient, (4) adaptive, (5) minimum disruptive, and (6) stable. The protocol extensions are addressed to support the proposed method. By exchanging the traffic demand matrix between border nodes, each border node determines the order nodded, to which it should set up the light-path.
  • Performance Evaluation of Light Path Routing Algorithms in Photonic Networks, KATAYAMA Masaru, OKI Eiji, SHIOMOTO Kohei, YAMANAKA Naoaki, IMAJUKU Wataru, Technical report of IEICE. PS, 102, 1, 37, 41,   2002 04 03 , http://ci.nii.ac.jp/naid/110004024863
    Summary:We propose OSPF extension and light path routing algorithms in photonic networks to resolve the RWA (Routing and Wavelength Assignment) problem. We extend OSPF to advertize the wavelength status and wavelength conversion status for each link. A light routing path is calcurated using them. In this paper, we describe the evaluation results of our light path routing algorithms.
  • Noise Characteristics of Coherent Optical Amplifier, Imajuku Wataru, Takada Atsushi, Yamabayashi Yoshiaki, Technical report of IEICE. OPE, 99, 465, 61, 66,   1999 11 26 , http://ci.nii.ac.jp/naid/110003303860
    Summary:Coherent optical amplifiers can principally breakthrough the standard quantum limit of the 3-dB noise figure imposed on conventional amplifiers such as laser and Raman amplifiers. This paper analyzes the noise characteristics of the coherent optical amplifier using Kerr medium theoretically and experimentally. In theoretical analysis, we derived the quantum Langevin equation of a lossy Kerr medium, and obtained the quantum field operator and the photon number variation of output signal. In experimental study, we utilized a nonlinear fiber Sagnac interferometer as optical gain medium and achieved stable optical amplification by locking optical phase between signal and pump using optical injection with compensation PLL. The electrical spectrum analyzer method was employed for the noise figure measurement. By using a high nonlinearity fiber with the length of 3 km, the loss coefficient of -0.7 dB/km, and the nonlinear coefficient of 15.8/W/km, we successfully obtained low-noise figure optical amplification under the standard quantum limit, 2.0-dB noise figure with 16-dB gain.
  • Higher Order Optical Path Accommodation and Evaluation for the Amount of Network Elements, Yamawaku Jun, Imajuku Wataru, Takada Atsushi, Okamoto Satoru, Morioka Toshio, Technical report of IEICE. OCS, 101, 394, 7, 12,   2001 10 19 , http://ci.nii.ac.jp/naid/110003286122
    Summary:To support large amount of data traffic, optical path routing nodes are required to route a large number of paths efficiently without increasing the number of NW elements such as optical switch ports and transmission fibers. In this paper, we introduce Higher Order Optical Path(HO-OP)that bundles several optical paths for the purpose of reducing network elements, and evaluate its merits by using path accommodation setting simulations. This method can decrease not only the number of switch ports but also NW total elements.
  • Multi-Layer Traffic Engineering in Photonic IP Networks, OKI Eiji, SHIOMOTO Kohei, OKAMOTO Satoru, IMAJUKU Wataru, YAMANAKA Naoaki, Technical report of IEICE. PS, 101, 584, 43, 46,   2002 01 18 , http://ci.nii.ac.jp/naid/110003183033
    Summary:Multi-layer traffic engineering, which yields the dynamic cooperation of IP and photonic layers, is required to provide IP services cost-effectively. This paper proposes a heuristic-based multi-layer topology design scheme that uses IP traffic measurements in generalized multi-protocol label switch (GMPLS). The proposed scheme yields the optimu optical label switch path (OLSP) network topology, i.e. OLSP placement, to minimize network cost, in response to fluctuations in IP traffic demand. In other words, OLSP network topology is dynamically reconfigured to match IP traffic demand. Networks reconfigured by the proposed scheme utilize the network resources cost-effectively.
  • Gain Characteristics of Phase-Sensitive Amplifier with Nonlinear Fiber Sagnac Interferometer, Imajuku W., Lim C.H., Takada A., Technical report of IEICE. OPE, 98, 415, 13, 18,   1998 11 19 , http://ci.nii.ac.jp/naid/110003303189
    Summary:This paper clarifies the relationship between optical gain and fiber parameters of optical phase-sensitive amplifier with nonlinear fiber Sagnac interferometer (NFSI-PSA) by both theoretical and experimental study. In the theoretical study, parametric process within nonlinear fiber Sagnac interferometer (NFSI) is described by the small-signal analysis to obtain optical gain. The results of the small-signal analysis well explain experimental results, which means the analysis is applicable to design NFSI-PSA. We also confirmed as high as 11 dB gain increment by using high nonlinearity silica fiber which is enhanced nonlinearity parameter 7 times larger than the conventional single mode silica fiber.
  • In-line Phase-Sensitive Amplifier With Phase-Locked Internal Pump Light Source, Takada Atsushi, Imajuku Wataru, Technical report of IEICE. OCS, 97, 408, 13, 18,   1997 11 28 , http://ci.nii.ac.jp/naid/110003285476
    Summary:Optical phase-sensitive amplifiers (PSAs) are promising as optical amplifier repeaters in fiber transmission system, because it has been shown theoretically that these have very low noise figures and waveform reshaping effect of chirped pulses. To realize in-line PSAs, the PSA requires internal light source generating pump light whose optical phase is locked to that of input signal light. The extended-ring cavity semiconductor laser with capability of frequency modulation and narrow linewidth-oscillation is developed as pump source and its optical phase is locked by two methods, optical signal injection and optical phase lock loop. By incorporating with degenerated parametric amplification in nonlinear fiber sagnac interferometer, in-line PSAs with internal phase-locked pump light source is successfully demonstrated.
  • The design of PSA repeated optical transmission systems reducing modulation instability, Imajuku Wataru, Takada Atsushi, Technical report of IEICE. OCS, 96, 538, 71, 76,   1997 02 21 , http://ci.nii.ac.jp/naid/110003285536
    Summary:The advent of erbium doped fiber amplifier achieved high-power and long regenerative repeater span optical transmission for high speed and long distance transmission systems. However, this simultaneously enhanced modulation instability originating from non-linear refractive index of transmission fiber. The signal-to-noise ratio (SNR) at receiver of NRZ optical transmission system tends to be degraded by modulation instability, especially for anomalous or zero dispersion fiber transmission systems. This study focuses on the application of phase-sensitive amplifier (PSA) as optical repeater in order to reduce modulation instability. Here, the SNR at receiver of PSA system was analyzed by including dispersion, dispersion slope, and non-linear refractive index of fiber. The results of these analyses indicate that PSA systems using zero dispersion fibercan effectively reduce modulation instability at the condition of high power optical transmission as high as 10 dBm.
  • Theoretical Study of Lightwave System using In-line Phase-Sensitive Amplifiers (PSAs), Imajuku W., Takada A., Technical report of IEICE. OCS, 96, 59, 29, 36,   1996 05 23 , http://ci.nii.ac.jp/naid/110003285622
    Summary:Reducing the degaradation of signal-to-noise ratio and of signal pulse form due to the combined effect of group velocity dispersion (GVD) and self-phase modulation (SPM) of transmission fiber is important issue to realize high-speend and long-span optical lightwave systems. In this report, the use of Phase-Sensitive Amplifiers as in-line repeater of the lightwave systems is theoretically studied to moderate those both of problems. In the discussion, higher order GVD and SPM are considerd to obtain the relationship between GVD, transmission speed and pulse shape limt, and then those results are compared between NRZ and RZ pulses. We also confirmed theoretically that the implementation of in-line PSAs expands regenarative repeater spacing about 10 times than that of EDFA systems, in case of TDM 40Gbit/s system.
  • Basic Characteristics of Phase-Sensitive Amplifier Using Fiber Nonlinear Optical Loop Mirror, Takada Atsushi, Imajuku Wataru, Technical report of IEICE. OCS, 96, 335, 7, 12,   1996 11 01 , http://ci.nii.ac.jp/naid/110003285581
    Summary:The characteristics of phase-sensitive amplifiers using optical Kerr material in interferometer are investigated theoretically and experimentally. Relationship between phase dependent gain, saturation output power, bandwidth and parameters of optical Kerr material used in the phase-sensitive amplifiers is clarified theoretically. It is shown theoretically that the maximum gain of 26 dB, bandwidth of 95 GHz, 3 dB saturation output power of 0.33 W are achieved for standard dispersion shifted fibers (DSFs) with 1 W pump power. Experimentally, the gain characteristics of optical fiber-nonlinear loop mirror employing polarization maintaining DSF are measured. The gain up to 23 dB is obtained and gain saturation due to input signal light are confirmed for the first time. The possibility of suppressing noise by utilizing the gain saturation is discussed.

Patents

  • Device and method for correcting a path trouble in a communication network, Wataru Imajuku, K. Shimano, Y. Takigawa, E. Oki, and Y. Okazaki, US Patent 8,134,920
  • Upper layer node, lower layer node, and node control method, N. Yamanaka, E. Oki, K. Shiomoto, S. Okamoto, Wataru Imajuku, US Patent 7,333,424
  • Node used in photonic network, and photonic network, E. Oki, Wataru Imajuku, K. Shiomoto, N. Yamanaka, D. Shimazaki, N. Nagatsu, Y. Takigawa, US Patent 7,313,328
  • Node, an optical/electrical path integrated network using the node, and a program which controls the node, E. Oki, K. Shiomoto, M. Katayama, Wataru Imajuku, US Patent 7,313,094
  • Optical path communication network, node, and optical path setup method, N. Matsuura, N. Yamanaka, Wataru Imajuku, E. Oki, US Patent 7,289,730
  • Method and apparatus for controlling optical wavelength based on optical frequency pulling, Wataru Imajuku, K. Yoshitada, US Patent 7,023,887
  • Optical parametric circuit, Wataru Imajuku, K. Mori, A. Takada, US Patent 7,012,740
  • Method and apparatus for controlling optical wavelength based on optical frequency pulling, Wataru Imajuku, K. Yoshitada, US Patent 6,909,732
  • Optical parametric circuit, Wataru Imajuku, K. Mori, and A. Takada, US Patent 6,867,903
  • Bit-phase synchronized optical pulse stream local generator, K. Uchiyama, E. Hashimoto, Wataru Imajuku, US Patent 6,560,007
  • Method and apparatus for controlling optical wavelength based on optical frequency pullin, Wataru Imajuku and Y. Katagiri, US Patent 6,370,169

Awards & Honors

  •   2015 06 , Nippon Telegraph and Telephone, Highest Grade President Patent Award
  •   2014 09 , APNOMS 2014, Best Paper Award
  •   2008 07 , OECC/IOOC 2007, Best Paper Award
  •   2003 09 , HPSR 2003, Best Paper Award
  •   2000 03 , IEICEJ, Young Research Engineer Paper Award

Research Grants & Projects

  • The Telecommunications Advancement Foundation, Research Grant, Research on Optical Transmission Technology with Nonlinear Line Codes, Imajuku, Wataru
  • Japan Science and Technology Agency, Research Grant (C), Research on Optical Transmission Technology with Gain Saturated Parametric Amplifier and Nonlinear Line Codes, Imajuku, Wataru
  • Iizuka City, Research Grant, Research on optical fiber sensing for simultaneous thermal and distortion change detection, Imajuku, Wataru
  • Private Company, Accession Research, Wavelength conversion circuit within optical node, Imajuku, Wataru
  • Private Company, Accession Research, nonlinear phase noise reduction circuit within optical node, Imajuku, Wataru
  • National Institute of Information and Communication Research, Accession Research, Research on elastic optical network architecture
  • Ministry of Internal Affairs and Communications, SCOPE: Strategic Information and Communications R&D Promotion Program, Standardization inter-carrier interface for optical networks