Takeshi UMEKI

Channel Arrangement Design in Lumped Amplified WDM Transmission over NZ-DSF Link with Nonlinearity Mitigation Using Optical Phase Conjugation
Shimpei SHIMIZU Takayuki KOBAYASHI Takeshi UMEKI Takushi KAZAMA Koji ENBUTSU Ryoichi KASAHARA Yutaka MIYAMOTO 
Publication:   
Publication Date: 2022/07/01
Vol. E105-B  No. 7  pp. 805-813
Type of Manuscript:  PAPER
Category: Fiber-Optic Transmission for Communications
Keyword: 
optical signal processing techniques for optical communications, optical phase conjugation, nonlinear optics, periodically poled LiNbO3 waveguide, 
 Summary | Full Text:PDF
Nonlinearity Mitigation of PDM-16QAM Signals Using Multiple CSI-OPCs in Ultra-Long-Haul Transmission without Excess Penalty
Takeshi UMEKI Takayuki KOBAYASHI Akihide SANO Takuya IKUTA Masashi ABE Takushi KAZAMA Koji ENBUTSU Ryoichi KASAHARA Yutaka MIYAMOTO 
Publication:   
Publication Date: 2020/11/01
Vol. E103-B  No. 11  pp. 1226-1232
Type of Manuscript:  Special Section PAPER (Joint Special Section on Opto-electronics and Communications for Future Optical Network)
Category: 
Keyword: 
optical signal processing techniques for optical communications, optical phase conjugation, nonlinear optics, periodically poled LiNbO3 waveguide, 
 Summary | Full Text:PDF
PPLN-Based Low-Noise Phase Sensitive Amplification Using an Optical Phase-Locked Pump
Takushi KAZAMA Takeshi UMEKI Yasuhiro OKAMURA Koji ENBUTSU Osamu TADANAGA Atsushi TAKADA Ryoichi KASAHARA 
Publication:   
Publication Date: 2020/11/01
Vol. E103-B  No. 11  pp. 1265-1271
Type of Manuscript:  Special Section PAPER (Joint Special Section on Opto-electronics and Communications for Future Optical Network)
Category: 
Keyword: 
phase sensitive amplifier, periodically poled LiNbO3 waveguide, noise figure, 
 Summary | Full Text:PDF
Phase Sensitive Amplifier Using Periodically Poled LiNbO3 Waveguides and Their Applications
Masaki ASOBE Takeshi UMEKI Osamu TADANAGA 
Publication:   
Publication Date: 2018/07/01
Vol. E101-C  No. 7  pp. 586-593
Type of Manuscript:  INVITED PAPER (Special Section on Distinguished Papers in Photonics)
Category: 
Keyword: 
optical amplifier, lithium niobate, quasi-phase marching, optical communication, 
 Summary | Full Text:PDF
PPLN-Based Low-Noise In-Line Phase Sensitive Amplifier with Highly Sensitive Carrier-Recovery System
Koji ENBUTSU Takeshi UMEKI Osamu TADANAGA Masaki ASOBE Hirokazu TAKENOUCHI 
Publication:   IEICE TRANSACTIONS on Communications
Publication Date: 2016/08/01
Vol. E99-B  No. 8  pp. 1727-1733
Type of Manuscript:  Special Section PAPER (Special Section on Advanced Information and Communication Technologies and Services in Conjunction with Main Topics of APCC2015)
Category: Fiber-Optic Transmission for Communications
Keyword: 
phase sensitive amplifier, periodically poled LiNbO3 waveguide, 
 Summary | Full Text:PDF