CA2051325A1 - Optical communication system - Google Patents

Optical communication system

Info

Publication number
CA2051325A1
CA2051325A1 CA2051325A CA2051325A CA2051325A1 CA 2051325 A1 CA2051325 A1 CA 2051325A1 CA 2051325 A CA2051325 A CA 2051325A CA 2051325 A CA2051325 A CA 2051325A CA 2051325 A1 CA2051325 A1 CA 2051325A1
Authority
CA
Canada
Prior art keywords
signal
optical
modulated
transmission signals
band
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA2051325A
Other languages
French (fr)
Other versions
CA2051325C (en
Inventor
Shigeki Watanabe
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu Ltd
Original Assignee
Shigeki Watanabe
Fujitsu Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP2242615A external-priority patent/JP2838839B2/en
Priority claimed from JP2282642A external-priority patent/JP2775692B2/en
Application filed by Shigeki Watanabe, Fujitsu Limited filed Critical Shigeki Watanabe
Publication of CA2051325A1 publication Critical patent/CA2051325A1/en
Application granted granted Critical
Publication of CA2051325C publication Critical patent/CA2051325C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0298—Wavelength-division multiplex systems with sub-carrier multiplexing [SCM]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/501—Structural aspects
    • H04B10/503—Laser transmitters
    • H04B10/504—Laser transmitters using direct modulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/501—Structural aspects
    • H04B10/503—Laser transmitters
    • H04B10/505—Laser transmitters using external modulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/501—Structural aspects
    • H04B10/503—Laser transmitters
    • H04B10/505—Laser transmitters using external modulation
    • H04B10/5051—Laser transmitters using external modulation using a series, i.e. cascade, combination of modulators
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/501—Structural aspects
    • H04B10/506—Multiwavelength transmitters
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/50—Transmitters
    • H04B10/572—Wavelength control

Abstract

At a transmitting end, transmission signals corresponding to more than one channel are allocated different microwave frequencies and carriers of the microwave frequencies are modulated with the transmission signals in modulators. A filter is placed in the preceding or succeeding stage of a respective modulator to band-limit a corresponding transmission signal before or after modulation. The band-limited and modulated transmission signals are combined to produce a microwave frequency-division multiplexed signal. The multiplexed signal modulates an optical frequency modulator to produce an optical modulated signal. The optical modulated signal is transmitted to the receiving end. At the receiving end, the optical signal transmitted from the transmitting end is detected and converted to an electrical signal. The channel components are extracted from the electrical signal by bandpass filters and then demodulated.
CA002051325A 1990-09-14 1991-09-13 Optical communication system Expired - Fee Related CA2051325C (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2242615A JP2838839B2 (en) 1990-09-14 1990-09-14 Optical communication system
JP02-242615 1990-09-14
JP02-282642 1990-10-20
JP2282642A JP2775692B2 (en) 1990-10-20 1990-10-20 Optical communication system

Publications (2)

Publication Number Publication Date
CA2051325A1 true CA2051325A1 (en) 1992-03-15
CA2051325C CA2051325C (en) 1999-06-29

Family

ID=26535842

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002051325A Expired - Fee Related CA2051325C (en) 1990-09-14 1991-09-13 Optical communication system

Country Status (3)

Country Link
US (1) US5896211A (en)
EP (4) EP0772313A3 (en)
CA (1) CA2051325C (en)

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Also Published As

Publication number Publication date
EP0772313A3 (en) 1997-09-03
EP0772312A3 (en) 1997-09-03
EP0772314A3 (en) 1997-09-03
EP0477699A3 (en) 1993-09-01
EP0772314A2 (en) 1997-05-07
CA2051325C (en) 1999-06-29
US5896211A (en) 1999-04-20
EP0772312A2 (en) 1997-05-07
EP0772313A2 (en) 1997-05-07
EP0477699A2 (en) 1992-04-01

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