US4584678A
Expired / Lapsed
US
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Contention-type data communication system
Assignee: Toshiba Corp
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Filing: 1984-04-30
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Granted: 1986-04-22
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Expires: 2004-04-30
Abstract
Abstract A contention-type data communication system such as an optical star-configured network comprises a plurality of stations connected with one another through data bus. To detect a signal collision quickly, each of the stations is arranged to transmit a collision-detecting packet which has a predetermined time length T 1 and a predetermined pulse pattern, and then transmit a data packet after a time interval T 2 . The number or pattern of pulses received during a time period T 1 +T 2 from the start of reception of a collision-detecting packet is compared with that of the self-transmitted collision-detecting packet so that the signal collision is detected when noncoincidence occurs.
Inventors
- 👤 Takeshi Ozeki
- 👤 Toshifumi Tamura
- 👤 Mutsumi Fujihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:20
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/44
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
118 words
In a contention-type data communication system wherein a plurality of stations are connected with one another through data bus, each of said stations being arrranged to monitor, through the data bus, a self data signal transmitted over the data bus, each station includes: means for transmitting a collision-detecting packet having a predetermined time length T 1 and a predetermined pulse pattern, and a data packet after a time period T 2 from the end of the transmission of the collision-detecting packet; and means for detecting a communication collision on the data bus in response to pulses received during a time period T 1 +T 2 from the start of reception of the collision-detecting packet through the data bus.
Claim 2
Dependent Claim
118 words
In a contention-type data communication system wherein a plurality of stations are connected with one another through data bus, each of said stations being arrranged to monitor, through the data bus, a self data signal transmitted over the data bus, each station includes: means for transmitting a collision-detecting packet having a predetermined time length T 1 and a predetermined pulse pattern, and a data packet after a time period T 2 from the end of the transmission of the collision-detecting packet; and means for detecting a communication collision on the data bus in response to pulses received during a time period T 1 +T 2 from the start of reception of the collision-detecting packet through the data bus.
Claim 3
Dependent Claim
90 words
A contention-type data communication system according to claim 1, wherein the data communication system is an optical star-configured network system having an optical star coupler to which said stations are connected via optical fibres as the data bus, and wherein the time period T 1 +T 2 is set longer than or equal to two times a signal propagating delay time between said star coupler and a station which is remotest from said star coupler such that every station can detect a signal collision before transmission of a data packet.
Claim 4
Dependent Claim
25 words
A contention-type data communication system according to claim 1, wherein the collision-detecting packet transmitted from each of said stations has a predetermined number of pulses.
Claim 5
Dependent Claim
25 words
A contention-type data communication system according to claim 1, wherein pulse patterns of the collision-detecting packets transmitted from said stations are different from each other.
Claim 6
Dependent Claim
20 words
A contention-type communication system according to claim 1, wherein the collision-detecting packet is divided into three or more time slots.
Claim 7
Dependent Claim
58 words
A contention-type data communication system according to claim 1, wherein the collision-detecting packet is divided into I slots, I representing an integer larger than an integer K which is determined by K=[log 2 (N-1)]+2 ([x] represents the maximum integer not exceeding x and N, the maximum number of said stations), and each of the slots has J pulses.
Claim 8
Dependent Claim
38 words
A contention-type data communication system according to claim 6, wherein the J pulses in each of the slots of the collision-detecting packet are position-modulated in accordance with a bit pattern of an address of each of said stations.
Claim 9
Dependent Claim
26 words
A contention-type data communication system according to claim 7, wherein a head time slot of the collision-detecting packet has a pulse pattern common to said stations.
Claim 10
Dependent Claim
36 words
A contention-type data communication system according to claim 6, wherein the J pulses in each of the slots are arranged at the front or rear half of the slot according to corresponding bit of the address.
Claim 11
Dependent Claim
47 words
A contention-type data communication system according to claim 1, wherein the collision-detecting packet is divided into slots and has a pulse pattern according to the address of the station, and wherein each of the slots has a number of pulses corresponding to the corresponding bit of address.
Claim 12
Dependent Claim
47 words
A contention-type data communication system according to claim 1, wherein said collision-detecting means in each of said stations is arranged to detect the collision on the basis of the number of pulses received during a predetermined time period after the start of reception of the collision-detecting packet.
Claim 13
Dependent Claim
43 words
A contention-type data communication system according to claim 1, wherein said collision-detecting means in each of said stations is arranged to detect the collision by comparing a pulse pattern of a received collision-detecting packet with a pulse pattern of a self-transmitting collision-detecting packet.
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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) | 1989-04-21 | 1989-10-21 | 1990-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-21 | 1993-10-21 | 1994-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-21 | 1997-10-21 | 1998-04-22 | $7700.00 | Window Closed / Lapsed |