US4975899A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical broadcast network
Assignee: British Telecommunications PLC
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Filing: 1988-01-05
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Granted: 1990-12-04
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Expires: 2008-01-05
Abstract
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.
Inventors
- 👤 David W. Faulkner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:37
CPC Classifications
H; H04; H04J; H04J14/00; H04J14/08; H04B; H04B10/00; H04B10/27; H04B10/272; H04B10/50; H04J3/00; H04J3/02; H04J3/06; H04J3/0635; H04J3/0682
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
138 words
In an optical communications network comprising: a central node having an optical transmitter and an optical receiver; a plurality of remote stations each having an optical transmitter and an optical receiver; and at least one optical fiber transmission medium coupled between the central node and the remote stations, said optical fiber transmission medium including a passive splitter arrangement having a ratio of 1:N and carrying multiplexed signals, the network being adapted for carrying return signals from the remote stations multiplexed passively onto said transmission medium, the improvement comprising: arranging the optical transmitter of each said remote station to transmit information by modulating a sequence of low duty cycle pulses, each transmitted pulse having a peak power of N times the maximum continuous power rating of the transmitter and operating for not more than 1/N of the total time.
Claim 2
Dependent Claim
138 words
In an optical communications network comprising: a central node having an optical transmitter and an optical receiver; a plurality of remote stations each having an optical transmitter and an optical receiver; and at least one optical fiber transmission medium coupled between the central node and the remote stations, said optical fiber transmission medium including a passive splitter arrangement having a ratio of 1:N and carrying multiplexed signals, the network being adapted for carrying return signals from the remote stations multiplexed passively onto said transmission medium, the improvement comprising: arranging the optical transmitter of each said remote station to transmit information by modulating a sequence of low duty cycle pulses, each transmitted pulse having a peak power of N times the maximum continuous power rating of the transmitter and operating for not more than 1/N of the total time.
Claim 3
Dependent Claim
27 words
A network as in claim 1 wherein the optical transmitter of each remote station is arranged to operate for much less than 1/N of the total time.
Claim 4
Dependent Claim
15 words
A network as claimed in any of claims 1 and 2 wherein N is 128.
Claim 5
Dependent Claim
35 words
A network as claimed in any of claims 1 and 2 wherein the optical transmitter of each remote station is arranged such that each transmitted pulse has a duration of not more than 1 nanosecond.
Claim 6
Dependent Claim
117 words
In an optical communications network comprising: a plurality of nodes each including an optical transmitter and an optical receiver; and an optical fiber transmission medium coupled to the plurality of nodes, said transmission medium allowing each node to communicate with every other node, said optical fiber transmission medium including a passive optical signal power divider arrangement having a ratio of 1:N and carrying multiplexed signals, the improvement comprising: arranging the optical transmitter of each said node to transmit information by modulating a sequence of low duty cycle pulses, each transmitted pulse having a peak power of N times the maximum continuous power rating of the transmitter and operating for not more than 1/N of the total time.
Claim 7
Dependent Claim
117 words
In an optical communications network comprising: a plurality of nodes each including an optical transmitter and an optical receiver; and an optical fiber transmission medium coupled to the plurality of nodes, said transmission medium allowing each node to communicate with every other node, said optical fiber transmission medium including a passive optical signal power divider arrangement having a ratio of 1:N and carrying multiplexed signals, the improvement comprising: arranging the optical transmitter of each said node to transmit information by modulating a sequence of low duty cycle pulses, each transmitted pulse having a peak power of N times the maximum continuous power rating of the transmitter and operating for not more than 1/N of the total time.
Claim 8
Dependent Claim
26 words
A network as in claim 5 wherein the optical transmitter of each node is arranged to operate for much less than 1/N of the total time.
Claim 9
Dependent Claim
16 words
A network as claimed in any one of claims 5 and 6 wherein N is 128.
Claim 10
Dependent Claim
35 words
A network as claimed in any one of claims 5 and 6 wherein the optical transmitter of each node is arranged such that each transmitted pulse has a duration of not more than 1 nanosecond.
Claim 11
Dependent Claim
147 words
An optical communications network comprising: a central node having an optical transmitter and an optical receiver arrangement, said central node optical receiver for detecting pules having a predetermined constant vale of peak power; a plurality of remote stations each having an optical transmitter and an optical receiver; at least one optical fiber transmission medium coupled between the central node and the remote stations, said optical fiber transmission medium including a passive splitter arrangement having a ratio of 1:N and carrying multiplexed signals, the network being adapted for carrying return signals from the remote stations multiplexed passively onto said transmission medium, the optical transmitter of each said remote station transmitting information by modulating a sequence of low duty cycle pulses, each transmitted pulse having a peak power of N times said predetermined constant value of peak power and operating for not more than 1/N of the total time.
Claim 12
Dependent Claim
147 words
An optical communications network comprising: a central node having an optical transmitter and an optical receiver arrangement, said central node optical receiver for detecting pules having a predetermined constant vale of peak power; a plurality of remote stations each having an optical transmitter and an optical receiver; at least one optical fiber transmission medium coupled between the central node and the remote stations, said optical fiber transmission medium including a passive splitter arrangement having a ratio of 1:N and carrying multiplexed signals, the network being adapted for carrying return signals from the remote stations multiplexed passively onto said transmission medium, the optical transmitter of each said remote station transmitting information by modulating a sequence of low duty cycle pulses, each transmitted pulse having a peak power of N times said predetermined constant value of peak power and operating for not more than 1/N of the total time.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |