Inventor
SEKIYA MOTOYOSHI
US113 patents
Patents
50 patentsUS9485554B1Nov 1, 2016
Methods and systems for using modulation frequencies for optical channel monitoring with periodic optical filtering
FUJITSU LTD60 citations98
US9112609B2Aug 18, 2015
Mitigation of polarization dependent loss in optical multi-carrier/super-channel transmission
FUJITSU LTD56 citations98
US5991477ANov 23, 1999
Optical transmission system, optical multiplexing transmission system, and related peripheral techniques
FUJITSU LTD80 citations97
US5909297AJun 1, 1999
Drift compensating circuit for optical modulators in an optical system
FUJITSU LTD70 citations97
US5815294ASep 29, 1998
Optical transmission system with transmission characteristic measuring device
FUJITSU LTD71 citations97
US5696614ADec 9, 1997
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD85 citations97
US6654561B1Nov 25, 2003
Method and apparatus for measuring optical signal-to-noise ratio, and pre-emphasis method and optical communication system each utilizing the method
FUJITSU LTD60 citations96
US6417945B2Jul 9, 2002
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD30 citations96
US6243176B1Jun 5, 2001
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD34 citations96
US5896217AApr 20, 1999
Optical transmission system, optical multiplexing transmission system, and related peripheral techniques
FUJITSU LTD46 citations96
US5870213AFeb 9, 1999
Optical transmission system, optical multiplexing transmission system, and related peripheral techniques
FUJITSU LTD51 citations96
US5760937AJun 2, 1998
Optical demultiplexer
FUJITSU LTD39 citations96
US5754322AMay 19, 1998
Optical transmission system, optical multiplexing transmission system, and related peripheral techniques
FUJITSU LTD43 citations96
US5636046AJun 3, 1997
Optical dispersion compensation method using transmissible band determined from synergetic effect of self phase modulation and group velocity dispersion
FUJITSU LTD48 citations96
US5612807AMar 18, 1997
Optical dispersion compensation method for shifting a zero dispersion wavelength of an optical fiber to compensate for dispersion in an optical system
FUJITSU LTD31 citations96
US5602666AFeb 11, 1997
Optical dispersion compensation method for shifting a zero dispersion wavelength of an optical fiber to compensate for dispersion in an optical system
FUJITSU LTD56 citations96
US7133610B1Nov 7, 2006
Optical sender, terminal device, and optical communication system each having the optical sender
FUJITSU LTD54 citations95
US5900959AMay 4, 1999
Optical transmitter, optical communication system and optical communication method
FUJITSU LTD70 citations95
US9197320B2Nov 24, 2015
System and method for monitoring polarization-dependent loss
FUJITSU LTD48 citations94
US6590686B1Jul 8, 2003
Optical transmitter
FUJITSU LTD66 citations94
US6839162B2Jan 4, 2005
Optical amplifying apparatus and optical communication system
FUJITSU LTD25 citations93
US5596448AJan 21, 1997
Dispersion compensator and optical amplifier
FUJITSU LTD45 citations93
US9485019B1Nov 1, 2016
Methods and systems for optical channel monitoring with periodic optical filtering of dual polarization signals
FUJITSU LTD20 citations92
US6570703B2May 27, 2003
Optical amplifying apparatus, optical amplifying method, and optical communication system
FUJITSU LTD25 citations92
US6411429B1Jun 25, 2002
Optical amplifying apparatus, wide-band optical amplifying apparatus, and optical communication system
FUJITSU LTD28 citations92
US6334004B1Dec 25, 2001
Optical modulator, bias control circuit therefor, and optical transmitter including the optical modulator
FUJITSU LTD34 citations92
US6229833B1May 8, 2001
Laser diode protecting circuit and laser driving current control circuit
FUJITSU LTD53 citations92
US6097746AAug 1, 2000
Laser diode protecting circuit
FUJITSU LTD26 citations92
US6483625B2Nov 19, 2002
WDM optical transmission apparatus
FUJITSU LTD25 citations91
US9837788B2Dec 5, 2017
Optical phase-sensitive amplifier with raman amplifier intermediate stage
FUJITSU LTD11 citations84
US9344194B2May 17, 2016
System and method for monitoring and control of an optical modulator for an M-QAM transmitter
FUJITSU LTD8 citations84
US7359645B2Apr 15, 2008
Dispersion compensating method, optical transmission system, and optical transmission apparatus
FUJITSU LTD17 citations84
US7248804B2Jul 24, 2007
Optical transmission device using a wide input dynamic range optical amplifier
FUJITSU LTD10 citations84
US7031049B2Apr 18, 2006
Loss point detecting method and distributed raman amplifier applying the same
FUJITSU LTD19 citations84
US9246624B1Jan 26, 2016
Low noise optical phase-sensitive amplifier for dual-polarization modulation formats
FUJITSU LTD9 citations83
US6501774B2Dec 31, 2002
Optical transmission apparatus for multiple wavelengths and optical transmission wavelength control method
FUJITSU LTD18 citations83
US6844961B2Jan 18, 2005
Method and apparatus for controlling Raman amplification using excitation light pulses of different wavelengths
FUJITSU LTD15 citations82
US6384943B2May 7, 2002
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD13 citations82
US6275314B1Aug 14, 2001
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD13 citations82
US6252688B1Jun 26, 2001
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD13 citations82
US6252687B1Jun 26, 2001
Optical wavelength multiplex transmission method and optical dispersion compensation method
FUJITSU LTD13 citations82
US7394993B2Jul 1, 2008
Dispersion compensation quantity setting method, receiving terminal station, and wavelength-multiplexing optical transmission system
FUJITSU LTD8 citations74
US7212285B2May 1, 2007
Optical measurement device
FUJITSU LTD8 citations74
US6930824B1Aug 16, 2005
Optical amplifier which compensates for dispersion of a WDM optical signal
FUJITSU LTD11 citations74
US9912435B2Mar 6, 2018
Nonlinear penalty estimation using spectral inversion in optical transport networks
FUJITSU LTD3 citations73
US9838253B2Dec 5, 2017
Object-oriented network virtualization
FUJITSU LTD4 citations73
US9768878B2Sep 19, 2017
Methods and systems for superchannel power pre-emphasis
FUJITSU LTD3 citations73
US9712249B2Jul 18, 2017
Methods and systems for superchannel subcarrier monitoring using amplitude modulated tones
FUJITSU LTD3 citations73
US9699074B2Jul 4, 2017
Efficient utilization of transceivers for shared restoration in flexible grid optical networks
FUJITSU LTD6 citations73
US9614638B2Apr 4, 2017
Methods and systems for periodic optical filtering to identify tone modulated optical signals
FUJITSU LTD4 citations73
Showing the top 50 of 113 patents by PatentIndex Score.