US4809264A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Collision signal detection system
Assignee: 3Com Corp
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Filing: 1987-08-07
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Granted: 1989-02-28
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Expires: 2007-08-07
Abstract
Abstract A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media includes a plurality of listening stations connected to the shared, multi-user, frequency-division-multiplexed transmission media. The listening stations receive and transmit signals including data signals within a databand. A collision signal means is associated with each of the plurality of listening stations for sending a collision enforcement signal from one of the plurality of listening stations to the other ones of the plurality of stations after a data collision has been detected at the first station, the collision enforcement signal having a frequency within the data band. A central station is provided with an input connected with the output of each of the listening stations and an output connected with the input of each of the listening stations with all signals passing through the central station. Signal detection means is provided in the central station for receiving an input signal and for detecting the collision enforcement signal.
Inventors
- 👤 Menachem Abraham
- 👤 Yoseph Linde
- 👤 Gordon C. Saussy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:45
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/40; H04L12/403; H04L12/2801; H04L12/407; H04L12/413
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
117 words
A collision signal detection system for shared-multi-user, frequency-division-multiplexed transmission media comprising: a plurality of stations connected to the shared, multi-user, frequency-division-multiplexer transmission media, receiving and transmitting signals including data signals within a databand; collision signal means associated with each of said plurality of stations for sending a collision enforcement signal from one of said plurality of stations to the other ones of the plurality of stations after a data collision has been detected at said one of said plurality of stations, said collision enforcement signals having a frequency within the data band; signal detection means associated with at least one of said plurality of stations for receiving an input signal and for detecting said collision enforcement signal.
Claim 2
Dependent Claim
117 words
A collision signal detection system for shared-multi-user, frequency-division-multiplexed transmission media comprising: a plurality of stations connected to the shared, multi-user, frequency-division-multiplexer transmission media, receiving and transmitting signals including data signals within a databand; collision signal means associated with each of said plurality of stations for sending a collision enforcement signal from one of said plurality of stations to the other ones of the plurality of stations after a data collision has been detected at said one of said plurality of stations, said collision enforcement signals having a frequency within the data band; signal detection means associated with at least one of said plurality of stations for receiving an input signal and for detecting said collision enforcement signal.
Claim 3
Dependent Claim
39 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 1 wherein: said at least one of said plurality of stations is a central station with all signals passing through said central station detection means.
Claim 4
Dependent Claim
26 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 1 wherein: each of said plurality of stations includes said detection means.
Claim 5
Dependent Claim
26 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 1 wherein, said signal detection means includes: means for recovering a carrier.
Claim 6
Dependent Claim
73 words
The collision signal detection means for shared, multi-user, frequency-division-multiplexed transmission media according to claim 1 wherein, said signal detection means includes: means for recovering a correct carrier from the transmitted data when there is only one of said plurality of stations transmitting and for producing a carrier at the correct frequency when there are multiple stations transmitting and to produce a carrier at the correct frequency when the collision enforcement signal is received.
Claim 7
Dependent Claim
31 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 5 wherein, said signal detection means further includes: means for shifting the phase of said recovered carrier.
Claim 8
Dependent Claim
34 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 6 wherein, said signal detection means further includes: means for multiplying the phase shifted recovered carrier with said input signal.
Claim 9
Dependent Claim
70 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 1 wherein, said signal detection means includes: means for detecting when one station is transmitting data and there is no collision, means for detecting when collision enforcement is being transmitted regardless of data transmission, and means for having a probability of detecting a collision condition when multiple stations are transmitting and there is no collision enforcement.
Claim 10
Dependent Claim
118 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media comprising: a plurality of stations, connected to the shared, multi-user, frequency-division-multiplexed transmission media, receiving and transmitting signals including data signals within a data band; a signal generator, associated with each of said plurality of stations, adapted to produce a collision enforcement signal having a frequency within the data band in response to the detection of a collision; and, detection means for detecting when one of station is transmitting data and there is no collision, for detecting when collision enforcement is being transmitted regardless of data transmission, and to have a probability of detecting a collision condition when multiple stations are transmitting and there is no collision enforcement.
Claim 11
Dependent Claim
118 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media comprising: a plurality of stations, connected to the shared, multi-user, frequency-division-multiplexed transmission media, receiving and transmitting signals including data signals within a data band; a signal generator, associated with each of said plurality of stations, adapted to produce a collision enforcement signal having a frequency within the data band in response to the detection of a collision; and, detection means for detecting when one of station is transmitting data and there is no collision, for detecting when collision enforcement is being transmitted regardless of data transmission, and to have a probability of detecting a collision condition when multiple stations are transmitting and there is no collision enforcement.
Claim 12
Dependent Claim
36 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 9 wherein: said detection means is associated with a single central station with all signals passing through said central station detection means.
Claim 13
Dependent Claim
26 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 9 wherein: each of said plurality of stations includes said detection means.
Claim 14
Dependent Claim
142 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media comprising: a plurality of listening stations connected to the shared, multi-user, frequency-division-multiplexer transmission media, receiving and transmitting signals including data signals within a databand; collision signal means associated with each of said plurality of listening stations for sending a collision enforcement signal from one of said plurality of listening stations to the other ones of the plurality of stations after a data collision has been detected at said one of said plurality of listening stations, said collision enforcement signal having a frequency within the data band; a central station having an input connected with the input of each of said listening stations with all signals passing through said central station; and, signal detection means associated with said central station for receiving an input signal and for detecting said collision enforcement signal.
Claim 15
Dependent Claim
142 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media comprising: a plurality of listening stations connected to the shared, multi-user, frequency-division-multiplexer transmission media, receiving and transmitting signals including data signals within a databand; collision signal means associated with each of said plurality of listening stations for sending a collision enforcement signal from one of said plurality of listening stations to the other ones of the plurality of stations after a data collision has been detected at said one of said plurality of listening stations, said collision enforcement signal having a frequency within the data band; a central station having an input connected with the input of each of said listening stations with all signals passing through said central station; and, signal detection means associated with said central station for receiving an input signal and for detecting said collision enforcement signal.
Claim 16
Dependent Claim
48 words
A collision signal detection system for shared, multi-user, frequency-division-multiplexed transmission media according to claim 12 further comprising: carrier detect means associated with each of said listening stations for continuously monitoring the transmission media for energy; RF carrier drop means associated with said central station for interrupting a carrier.
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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) | 1992-02-28 | 1992-08-29 | 1993-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-02-28 | 1996-08-29 | 1997-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-02-28 | 2000-08-29 | 2001-02-28 | $7700.00 | Window Closed / Lapsed |