Inventor
TAKEYARI RYOJI
JP30 patents
Patents
30 patentsUS5612959AMar 18, 1997
Multicast communications method
HITACHI LTD164 citations98
US5555477ASep 10, 1996
Optical transmission system constructing method and system
HITACHI LTD48 citations96
US5510921AApr 23, 1996
Optical frequency division multiplexing network
HITACHI LTD72 citations96
US5323258AJun 21, 1994
Homodyne optical receiver equipment
HITACHI LTD84 citations96
US5438444AAug 1, 1995
Optical routing system
HITACHI LTD64 citations93
US7099596B2Aug 29, 2006
Optical transmitter
HITACHI LTD20 citations92
US6850713B2Feb 1, 2005
Optical single sideband transmitter
HITACHI LTD44 citations92
US6587260B2Jul 1, 2003
Band-expanding method for optical amplifiers and optical transmission apparatus
HITACHI LTD21 citations92
US6304357B1Oct 16, 2001
Optical receiver
HITACHI LTD43 citations92
US6266169B1Jul 24, 2001
Optical transmission equipment which transmits an amplified optical data signal and an optical surveillance signal
HITACHI LTD21 citations92
US6005699ADec 21, 1999
Optical wavelength multiplexing system
HITACHI LTD21 citations92
US5844445ADec 1, 1998
Feedback type pre-amplifier
HITACHI LTD33 citations92
US5812289ASep 22, 1998
Optical repeater and optical transmitter
HITACHI LTD23 citations92
US5321540AJun 14, 1994
Optical frequency division multiplexing network
HITACHI LTD20 citations92
US5838475ANov 17, 1998
Optical regenerator and an optical transmission system
HITACHI LTD27 citations88
US6658217B2Dec 2, 2003
Optical receiver
HITACHI LTD16 citations83
US6619865B1Sep 16, 2003
Optical frequency division multiplexing network
HITACHI LTD11 citations82
US5861972AJan 19, 1999
Optical multiplex transmission equipment and method
HITACHI LTD12 citations82
US5142402AAug 25, 1992
Polarization diversity optical receiving apparatus and method
HITACHI LTD20 citations82
US6728489B2Apr 27, 2004
Optical transmission system constructing method and system
HITACHI LTD6 citations74
US6018405AJan 25, 2000
Optical transmission equipment which transmits an amplified optical data signal and an optical surveillance signal
HITACHI LTD7 citations74
US5875046AFeb 23, 1999
Optical repeater and optical transmitter
HITACHI LTD9 citations74
US5801864ASep 1, 1998
Optical frequency division multiplexing network
HITACHI LTD9 citations74
US5739932AApr 14, 1998
Optical transmission system constructing method and system
HITACHI LTD8 citations74
US5506711AApr 9, 1996
Star type multi-stage network
HITACHI LTD18 citations74
US5576876ANov 19, 1996
Optical regenerator and an optical transmission system
HITACHI LTD12 citations69
US7292785B2Nov 6, 2007
Optical transmission system constructing method and system
HITACHI LTD2 citations63
US7167652B2Jan 23, 2007
Optical transmission system constructing method and system
HITACHI LTD1 citations63
US7127170B2Oct 24, 2006
Optical frequency division multiplexing network
HITACHI LTD0 citations52
US6931039B2Aug 16, 2005
Optical transmitter equipment and semiconductor laser device
HITACHI LTD0 citations41