AU585188B2 – An optical broadcast network
– Google Patents
AU585188B2 – An optical broadcast network
– Google Patents
An optical broadcast network
Info
Publication number
AU585188B2
AU585188B2
AU10882/88A
AU1088288A
AU585188B2
AU 585188 B2
AU585188 B2
AU 585188B2
AU 10882/88 A
AU10882/88 A
AU 10882/88A
AU 1088288 A
AU1088288 A
AU 1088288A
AU 585188 B2
AU585188 B2
AU 585188B2
Authority
AU
Australia
Prior art keywords
optical
broadcast network
optical transmitter
transmitter
power
Prior art date
1987-01-05
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.)
Ceased
Application number
AU10882/88A
Other versions
AU1088288A
(en
Inventor
David Wynford Faulkner
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.)
British Telecommunications PLC
Original Assignee
British Telecommunications PLC
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.)
1987-01-05
Filing date
1988-01-05
Publication date
1989-06-08
1988-01-05
Application filed by British Telecommunications PLC
filed
Critical
British Telecommunications PLC
1988-07-27
Publication of AU1088288A
publication
Critical
patent/AU1088288A/en
1989-06-08
Application granted
granted
Critical
1989-06-08
Publication of AU585188B2
publication
Critical
patent/AU585188B2/en
2008-01-05
Anticipated expiration
legal-status
Critical
Status
Ceased
legal-status
Critical
Current
Links
Espacenet
Global Dossier
Discuss
Classifications
H—ELECTRICITY
H04—ELECTRIC COMMUNICATION TECHNIQUE
H04J—MULTIPLEX COMMUNICATION
H04J14/00—Optical multiplex systems
H04J14/08—Time-division multiplex systems
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
H04B10/27—Arrangements for networking
H04B10/272—Star-type networks or tree-type networks
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
H04J—MULTIPLEX COMMUNICATION
H04J3/00—Time-division multiplex systems
H04J3/02—Details
H04J3/06—Synchronising arrangements
H04J3/0635—Clock or time synchronisation in a network
H04J3/0682—Clock or time synchronisation in a network by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
Abstract
An optical braodcast network comprises a number of remote stations (5) connected to a node (1) by optical fibre transmission paths (2,4) interconnected by optical power dividers (3), each remote station including an optical transmitter operating at a high peak power and a low duty cycle for a short period. Typically the optical transmitter is enabled to transmit information for only 10% or less of the total time and for a maximum time of 500 ns.
Description
An optical Broadcast Network
This invention relates to an optical broadcast network in which optical signals in the form of pulses of light are broadcast over optical fibre transmission paths. Usually optical broadcast networks are used to transmit information at high speed between two nodes and are used to convey large volumes of information. The electro-optic devices which are used as transmitters in such systems usually have the form of semiconductor lasers and are part of sophisticated equipment including control circuitry to control the output of the laser as well as a heat sink and cooling arrangements to prevent the transmitter from overheating. The signal transmitted by such a transmitter may well be a time division multiplex signal so that a large number of different channels of information are transmitted simultaneously over the same optical fibre transmission path but, in this case, all of these channels of information are transmitted by the same optical transmitter.
According to this invention an optical broadcast network comprises a number of remote stations connected to a node by optical fibre transmission paths interconnected by optical power dividers, each remote station including an optical transmitter operating at a high peak power and a low duty cycle.
Typically by a low duty cycle the optical transmitter is enabled to transmit information for only 10% or less of the total time and for a maximum time of 500 ns. This is very much less than conventional optical transmitters which are able to transmit information for 100% of the time but, for, typically 50% of that time are operating to transmit data represented by no pulse of light. Preferably the information is transmitted for a maximum time of 250 ns and typically for 60 ns when the
power divider has a splitting ratio of 1:128. It is also possible to transmit for periods as short as 0.5 or 1 ns. With an arrangement in accordance with this invention it is preferred that the optical broadcast network operates an optical time division multiplex system between the node and the number of remote stations with each remote station being enabled to transmit in its own, individual time slot so that the optical signals from the remote stations interleave with one another at the node. One way, and the preferred way, in which the present invention can be used is to operate the optical transmitter at a high peak power many times greater than its maximum continuous power rating but, below its power damage rating under pulsed conditions. When, for example, the optical transmitter is operating a 10% duty cycle with a short period it is possible for the peak output power to be increased to ten times the maximum continuous power rating for the transmitter whilst still providing only the same thermal dissipation, assuming that the optical transmitter has a linear power to drive current relationship.
With such an arrangement it is possible to get a substantially constant received signal at the node no matter what splitting ratio is adopted in the optical power dividers by simply increasing the power of the optical transmitter in inverse proportion to the splitting ratio. Also with this arrangement failures can be readily identified. For example, the optical transmitter is permanently turned ON either it fails catastrophically or a fuse or other protective, element. in series with the device isolates it within a short period of time or its optical output reduces so that it is immediately apparent at the receiving node that a failure has occurred because the output of one transmitter is very low.
Another way in which the present invention can be used is for the high peak power at which the optical transmitter of the remote station operates to be the maximum continuous rating of the optical transmitter. With this arrangement only a fraction of the normal heat load on the optical transmitter is generated and this reduces the need for a heat sink, allows the optical device to operate at a lower internal temperature at which it is more efficient, and usually eliminates the need for external or internal cooling devices. It also improves the life of the optical transmitter.
Depending upon the application it is possible to arrange for both of these groups of advantages to be gained simultaneously and thus, with a very short duty cycle of, for example, only 1% it would be possible to have an optical transmitter operating at ten times its maximum continuous rating but, at the same time, only dissipate 10% of the heat that it would generate if run continuously at its maximum rating and have its life increased, typically by ten times.
Two particular examples of optical broadcast networks in accordance with this invention will now be described with reference to the accompanying drawings, in which:- Figure 1 is a diagram of a first network; and,
Figure 2 is a diagram of part of a second network.
The first example represents a conventional time division multiplex transmission system with transmissions from a central controlling node 1 taking place over a first optical fibre transmission line 2 to . an optical power divider 3. The signal power is divided in the divider 3 between N optical fibre transmission lines 4 which lead to N remote stations 5. Information is transmitted continuously over the transmission paths 2 and 4 to all of the remote stations 5 but, as usual in
conventional time division multiplex systems, each remote station is enabled to receive only the information transmitted during its own time slot. The remote stations 5 communicate with the controlling node 1 by transmitting over the same optical fibre transmission paths 2 and 4, or alternatively over different optical fibre transmission paths with each remote station 5 being enabled to transmit only during its own predetermined transmission time slot. Typically the maximum time for which each remote station transmitter operates is 1/N of the total time and it may be much less than this. Each remote station 5 transmits information by modulating a sequence of low duty cycle pulses.
The second example which is shown in Figure 2 allows each node to broadcast to every other node without the need for common control. Each node is allocated time slots in which it can transmit modulated low duty cycle pulses and these pulses form a time division multiplex in the optical signal power divider 3 which is received by other nodes on the network.
Claims (7)
1. An optical broadcast network comprising a number of remote stations connected to a node by optical fibre transmission paths interconnected by optical power dividers, each remote station including an optical transmitter operating at a high peak power and at a low duty cycle.
2. An optical broadcast network according to claim 1, in which the optical transmitter is enabled to transmit information for substantially 10% or less of the total time and for a maximum time of 500 ns .
3. An optical broadcast network according to claim 2, in which the optical transmitter is enabled to transmit information for a maximum time of substantially 60 ns.
4. An optical broadcast network according to claim 2 or 3, in which the optical transmitter is enabled to transmit information for substantially 1% of the total time.
5. An optical broadcast network according to any one of the preceding claims, in which the optical transmitter operates at a high peak power many times greater than its maximum continuous power rating but, below its instantaneous power damage rating.
6. An optical broadcast network according to any one of claims 1 to 4 in which the high peak power of optical transmitter of the remote station is the maximum continuous rating of the optical transmitter.
7. An optical broadcast network substantially as described with reference to the accompanying drawings. .
AU10882/88A
1987-01-05
1988-01-05
An optical broadcast network
Ceased
AU585188B2
(en)
Applications Claiming Priority (2)
Application Number
Priority Date
Filing Date
Title
GB8700069
1987-01-05
GB8700069
1987-01-05
Publications (2)
Publication Number
Publication Date
AU1088288A
AU1088288A
(en)
1988-07-27
AU585188B2
true
AU585188B2
(en)
1989-06-08
Family
ID=10610251
Family Applications (1)
Application Number
Title
Priority Date
Filing Date
AU10882/88A
Ceased
AU585188B2
(en)
1987-01-05
1988-01-05
An optical broadcast network
Country Status (10)
Country
Link
US
(1)
US4975899A
(en)
EP
(1)
EP0276905B1
(en)
JP
(1)
JPH01502469A
(en)
AT
(1)
ATE95355T1
(en)
AU
(1)
AU585188B2
(en)
CA
(1)
CA1314935C
(en)
DE
(1)
DE3884414T2
(en)
ES
(1)
ES2045095T3
(en)
HK
(1)
HK135096A
(en)
WO
(1)
WO1988005232A1
(en)
Families Citing this family (32)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
JPH02120706A
(en)
*
1988-10-31
1990-05-08
Sumitomo Electric Ind Ltd
Optical transmission path
IT1252576B
(en)
*
1991-12-20
1995-06-19
Italtel Spa
PASSIVE OPTICAL NETWORK STRUCTURE WITH HIGH FAILURE INSENSITIVITY
US5189671A
(en)
*
1991-12-20
1993-02-23
Raynet Corporation
Apparatus and method for formatting variable length data packets for a transmission network
SE500320C2
(en)
*
1992-08-31
1994-05-30
Televerket
Device at telecommunication networks for distributing / controlling one or more information channels in the network and method for establishing communication networks
US5519830A
(en)
*
1993-06-10
1996-05-21
Adc Telecommunications, Inc.
Point-to-multipoint performance monitoring and failure isolation system
ES2076103B1
(en)
*
1993-08-20
1997-10-16
Alcatel Standard Electrica
DIGITAL COMMUNICATIONS SYSTEM WITH MULTIPLE ACCESS BY DIVISION IN TIME THROUGH FIBER OPTICS.
US6334219B1
(en)
1994-09-26
2001-12-25
Adc Telecommunications Inc.
Channel selection for a hybrid fiber coax network
USRE42236E1
(en)
1995-02-06
2011-03-22
Adc Telecommunications, Inc.
Multiuse subcarriers in multipoint-to-point communication using orthogonal frequency division multiplexing
US7280564B1
(en)
1995-02-06
2007-10-09
Adc Telecommunications, Inc.
Synchronization techniques in multipoint-to-point communication using orthgonal frequency division multiplexing
US7606492B2
(en)
2000-10-04
2009-10-20
Enablence Usa Fttx Networks Inc.
System and method for communicating optical signals upstream and downstream between a data service provider and subscribers
US7130541B2
(en)
*
2000-10-04
2006-10-31
Wave7 Optics, Inc.
System and method for communicating optical signals upstream and downstream between a data service provider and subscriber
US6973271B2
(en)
*
2000-10-04
2005-12-06
Wave7 Optics, Inc.
System and method for communicating optical signals between a data service provider and subscribers
KR20030064775A
(en)
*
2000-10-26
2003-08-02
웨이브7 옵틱스 인코포레이티드
Method and system for processing downstream packets of an optical network
US7877014B2
(en)
2001-07-05
2011-01-25
Enablence Technologies Inc.
Method and system for providing a return path for signals generated by legacy video service terminals in an optical network
US7529485B2
(en)
*
2001-07-05
2009-05-05
Enablence Usa Fttx Networks, Inc.
Method and system for supporting multiple services with a subscriber optical interface located outside a subscriber’s premises
WO2003005612A1
(en)
*
2001-07-05
2003-01-16
Wave7 Optics, Inc.
Methods and systems for providing return path for signals generated by legacy terminals in optical network
US7190901B2
(en)
*
2001-07-05
2007-03-13
Wave7 Optices, Inc.
Method and system for providing a return path for signals generated by legacy terminals in an optical network
WO2003005611A2
(en)
*
2001-07-05
2003-01-16
Wave7 Optics, Inc.
System and method for communicating optical signals to multiple subscribers having various bandwidth demands connected to the same optical waveguide
US7333726B2
(en)
*
2001-07-05
2008-02-19
Wave7 Optics, Inc.
Method and system for supporting multiple service providers within a single optical network
US6654565B2
(en)
2001-07-05
2003-11-25
Wave7 Optics, Inc.
System and method for increasing upstream communication efficiency in an optical network
US7146104B2
(en)
2001-07-05
2006-12-05
Wave7 Optics, Inc.
Method and system for providing a return data path for legacy terminals by using existing electrical waveguides of a structure
US7269350B2
(en)
*
2001-07-05
2007-09-11
Wave7 Optics, Inc.
System and method for communicating optical signals between a data service provider and subscribers
US20030072059A1
(en)
*
2001-07-05
2003-04-17
Wave7 Optics, Inc.
System and method for securing a communication channel over an optical network
US7593639B2
(en)
2001-08-03
2009-09-22
Enablence Usa Fttx Networks Inc.
Method and system for providing a return path for signals generated by legacy terminals in an optical network
US7038910B1
(en)
2002-01-07
2006-05-02
Wave7 Optics, Inc.
System and method for removing heat from a subscriber optical interface
US7583897B2
(en)
2002-01-08
2009-09-01
Enablence Usa Fttx Networks Inc.
Optical network system and method for supporting upstream signals propagated according to a cable modem protocol
US7623786B2
(en)
*
2002-05-20
2009-11-24
Enablence Usa Fttx Networks, Inc.
System and method for communicating optical signals to multiple subscribers having various bandwidth demands connected to the same optical waveguide
US7058260B2
(en)
2002-10-15
2006-06-06
Wave7 Optics, Inc.
Reflection suppression for an optical fiber
US7454141B2
(en)
2003-03-14
2008-11-18
Enablence Usa Fttx Networks Inc.
Method and system for providing a return path for signals generated by legacy terminals in an optical network
CA2576944A1
(en)
2004-08-10
2006-02-23
Wave7 Optics, Inc.
Countermeasures for idle pattern srs interference in ethernet optical network systems
US7599622B2
(en)
2004-08-19
2009-10-06
Enablence Usa Fttx Networks Inc.
System and method for communicating optical signals between a data service provider and subscribers
US7616901B2
(en)
2005-08-10
2009-11-10
Enablence Usa Fttx Networks Inc.
Countermeasures for idle pattern SRS interference in ethernet optical network systems
Citations (3)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
AU6379086A
(en)
*
1985-09-25
1987-04-24
Telstra Corporation Limited
Optical distribution system
AU8121387A
(en)
*
1986-11-13
1988-05-19
Overseas Telecommunications Commission (Australia)
Optical fibre communication system
AU1081488A
(en)
*
1987-01-05
1988-07-27
British Telecommunications Public Limited Company
Optical communications network
Family Cites Families (10)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
US3315177A
(en)
*
1962-04-05
1967-04-18
Robert C Benson
Laser generator
CH564889A5
(en)
*
1973-11-28
1975-07-31
Patelhold Patentverwertung
US4047117A
(en)
*
1974-01-17
1977-09-06
Hughes Aircraft Company
Multi-level laser illuminator
FR2467524A1
(en)
*
1979-10-10
1981-04-17
Thomson Csf Mat Tel
METHOD OF SWITCHING MULTIPLEX SIGNALS TEMPORALLY AND TRANSMITTED BY A CARRIER WAVE, IN PARTICULAR A LIGHT WAVE, AND DEVICE FOR IMPLEMENTING THE SAME
US4302835A
(en)
*
1980-01-24
1981-11-24
Sperry Corporation
Multiple terminal passive multiplexing apparatus
US4399564A
(en)
*
1980-02-19
1983-08-16
The United States Of America As Represented By The Secretary Of The Navy
Fiber optic system for transmission of video signals by pulse-frequency-modulation
JPS59165537A
(en)
*
1983-03-10
1984-09-18
Nec Corp
Light star repeater
US4628501A
(en)
*
1983-12-29
1986-12-09
The United States Of America As Represented By The Secretary Of The Army
Optical communications systems
JPS61236229A
(en)
*
1985-04-12
1986-10-21
Matsushita Electric Ind Co Ltd
Optical space transmitter
US4775971A
(en)
*
1986-03-27
1988-10-04
American Telephone And Telegraph Company, At&T Bell Laboratories
Optical communication system
1988
1988-01-04
CA
CA000555763A
patent/CA1314935C/en
not_active
Expired – Fee Related
1988-01-05
DE
DE88300052T
patent/DE3884414T2/en
not_active
Expired – Fee Related
1988-01-05
AU
AU10882/88A
patent/AU585188B2/en
not_active
Ceased
1988-01-05
JP
JP63500746A
patent/JPH01502469A/en
active
Pending
1988-01-05
WO
PCT/GB1988/000003
patent/WO1988005232A1/en
unknown
1988-01-05
AT
AT88300052T
patent/ATE95355T1/en
not_active
IP Right Cessation
1988-01-05
ES
ES88300052T
patent/ES2045095T3/en
not_active
Expired – Lifetime
1988-01-05
EP
EP88300052A
patent/EP0276905B1/en
not_active
Expired – Lifetime
1988-01-05
US
US07/235,873
patent/US4975899A/en
not_active
Expired – Fee Related
1996
1996-07-25
HK
HK135096A
patent/HK135096A/en
not_active
IP Right Cessation
Patent Citations (3)
* Cited by examiner, † Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
AU6379086A
(en)
*
1985-09-25
1987-04-24
Telstra Corporation Limited
Optical distribution system
AU8121387A
(en)
*
1986-11-13
1988-05-19
Overseas Telecommunications Commission (Australia)
Optical fibre communication system
AU1081488A
(en)
*
1987-01-05
1988-07-27
British Telecommunications Public Limited Company
Optical communications network
Also Published As
Publication number
Publication date
ES2045095T3
(en)
1994-01-16
EP0276905B1
(en)
1993-09-29
EP0276905A1
(en)
1988-08-03
DE3884414T2
(en)
1994-03-03
ATE95355T1
(en)
1993-10-15
AU1088288A
(en)
1988-07-27
DE3884414D1
(en)
1993-11-04
HK135096A
(en)
1996-08-02
US4975899A
(en)
1990-12-04
WO1988005232A1
(en)
1988-07-14
CA1314935C
(en)
1993-03-23
JPH01502469A
(en)
1989-08-24
Similar Documents
Publication
Publication Date
Title
AU585188B2
(en)
1989-06-08
An optical broadcast network
US4709416A
(en)
1987-11-24
Laser bias current stabilization for burst mode fiber optic communication system
US5118964A
(en)
1992-06-02
Thermo-electric temperature control arrangement for laser apparatus
US5898801A
(en)
1999-04-27
Optical transport system
US5319486A
(en)
1994-06-07
Transmission equipment with an optical transmission line
US5631757A
(en)
1997-05-20
Full-duplex data communication system using different transmit and receive data symbol lengths
EP0314724A1
(en)
1989-05-10
Control of optical systems.
US5854699A
(en)
1998-12-29
Multiplexed subcarrier control in wavelength division multiplexed broadband networks
US6675072B1
(en)
2004-01-06
Transmission systems and components utilizing thermo-stabilization and methods of use therein
US5457555A
(en)
1995-10-10
Optical transmission system
KR100272709B1
(en)
2000-11-15
Apparatus and method transmission control in a optical wdm
US5027434A
(en)
1991-06-25
Apparatus for bidirectional transmission of optical signals
US6107850A
(en)
2000-08-22
Output pulse width control system
KR940017431A
(en)
1994-07-26
Locale communication system with multiple data channels and apparatus for use in the system
US4046959A
(en)
1977-09-06
Data communication system using photocouplers
GB1394075A
(en)
1975-05-14
Extendable mult'plexer
JP2003110505A
(en)
2003-04-11
Optical transmitter and wavelength division multiplexing transmission system
US4633525A
(en)
1986-12-30
Light-emitting diode device for suppressing thermal time-constant effects
JPH01166578A
(en)
1989-06-30
Led driving circuit with temperature control function
US5394419A
(en)
1995-02-28
Circuit arrangement for limiting the power of the optical signal emitted by a laser diode
US7068693B2
(en)
2006-06-27
Laser driver circuit for burst mode transmission
JPH08274719A
(en)
1996-10-18
Optical output control circuit of optical communication system
JPS6161535A
(en)
1986-03-29
Optical transmitter
JP3352294B2
(en)
2002-12-03
Wavelength control method and communication terminal station using the same
JPS6146619A
(en)
1986-03-06
Circuit device for driving thyristor
Legal Events
Date
Code
Title
Description
2003-08-14
MK14
Patent ceased section 143(a) (annual fees not paid) or expired