P

Inventor

TAKASAKI YOSHITAKA

JP32 patents

Patents

32 patents
US5042027AAug 20, 1991

Communication network system and method of controlling a communication network

HITACHI LTD369 citations98
US4604745AAug 5, 1986

Method of searching fault locations in digital transmission line

HITACHI LTD59 citations96
US4459698AJul 10, 1984

Variable equalizer

HITACHI LTD79 citations96
US5140453AAug 18, 1992

Optical receiving method utilizing polarization diversity and apparatus for carrying out the same

HITACHI LTD32 citations92
US5121244AJun 9, 1992

Optical subscriber network transmission system

HITACHI LTD53 citations92
US5113524AMay 12, 1992

Quantum state control apparatus, optical receiver and optical communication system

HITACHI LTD40 citations92
US4123242AOct 31, 1978

Apparatus for producing optical fiber

HITACHI LTD32 citations92
US4187479AFeb 5, 1980

Variable equalizer

HITACHI LTD55 citations91
US5815502ASep 29, 1998

Information transmission system with variable transmission rate

HITACHI LTD16 citations82
US5515368AMay 7, 1996

Information transmission system with variable transmission rate

HITACHI LTD16 citations82
US4967410AOct 30, 1990

Method of multiplexing digital signals and apparatus therefor

HITACHI LTD20 citations82
US4504943AMar 12, 1985

Time domain multiplexer

HITACHI LTD25 citations82
US4410980AOct 18, 1983

Time division multiplexing system

HITACHI LTD24 citations82
US4004253AJan 18, 1977

Variable equalizer

HITACHI LTD23 citations81
US4723312AFeb 2, 1988

Light emitting diode driver circuit

HITACHI LTD24 citations80
US5175639ADec 29, 1992

Optical subscriber network transmission system

HITACHI LTD19 citations74
US5121381AJun 9, 1992

Optical switching apparatus for digital signal cross connection and method of interswitch optical transmission of digital signals

HITACHI LTD13 citations74
US5023604AJun 11, 1991

Communication system

HITACHI LTD13 citations74
US4970719ANov 13, 1990

Digital signal multiplexing apparatus

HITACHI LTD9 citations74
US4320527AMar 16, 1982

Bit synchronizing system for pulse signal transmission

HITACHI LTD14 citations74
US4204176AMay 20, 1980

Variable equalizer

HITACHI LTD7 citations73
US4503546AMar 5, 1985

Pulse signal transmission system

HITACHI LTD11 citations72
US4122417AOct 24, 1978

Variable equalizer

HITACHI LTD12 citations72
US4080580AMar 21, 1978

Variable equalizer

HITACHI LTD9 citations72
US4330856AMay 18, 1982

Digital signal transmission system including means for converting asynchronous signals to the operating speed of a transmission line

HITACHI LTD14 citations70
US5430733AJul 4, 1995

Digital transmission system for multiplexing and demultiplexing signals

HITACHI LTD5 citations63
US5418405AMay 23, 1995

Installation path network for distribution area

HITACHI LTD3 citations63
US5369517ANov 29, 1994

Optical subscriber network transmission system

HITACHI LTD3 citations63
US4796281AJan 3, 1989

Digital signal transmission system

HITACHI LTD4 citations63
US4262263AApr 14, 1981

Variable equalizer

HITACHI LTD2 citations63
US5414739AMay 9, 1995

Transmission system constituted of multistage reproduction nodes

HITACHI LTD6 citations62
US4097824AJun 27, 1978

Variable equalizer

HITACHI LTD2 citations62