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US5214645A Expired / Lapsed US ⏱️ 0.0 years remaining

TDM system and method having time slot request signaling

Assignee: Nokia Bell Labs
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Filing: 1990-06-06
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Granted: 1993-05-25
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Expires: 2010-06-06
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Abstract

Abstract A multi-user Time Division Multiplex (TDM) system includes a plurality of stations connected by one or more unidirectional data buses. A "queue of request" (QR) counter is added to each station having destination slot release capability (erasure station). The QR count indicates how many idle time slots on a first channel have been released by an erasure station. The QR counter is incremented when that station becomes active (i.e., has a data transmit request) and when a request bit on a second channel has been erased by that erasure station. The QR counter is decremented when a used time slot on the first channel is released to an idle time slot condition as long an outstanding requests exist from downstream stations. When the QR count is negative (indicating more released time slots than erased requests) that station erases a request signal on the channel opposite the channel when the time slot was released. When the QR count is positive (indicating that there are fewer released time slots than the total number of received and erasure station request signals), that station writes an additional request signal to its respective upstream or downstream stations. When the QR count is zero, request signals are not altered by that station. A separate QR counter and associated circuitry is utilized by each unidirectional bus of the TDM system.

Inventors

  • 👤 Hassan Hagirahim

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 07:55
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04J; H04J3/00; H04J3/16; H04J3/1682; H04L; H04L12/00; H04L12/28; H04L12/2852; H04J2203/00; H04J2203/0001; H04J2203/0046; H04J2203/0048; H04J2203/005; H04J2203/0064; H04J2203/0066

Claims Analysis

Total Claims: 32
Claim 1
Independent Claim 127 words
A station for use in a time division multiplex (TDM) communication system including a plurality of stations communicating over first and second unidirectional communication channels, said station having the capability of converting read time slots into idle time slots and comprising queue of request QR counter means for establishing a QR count indicating how many time slots over said first channel from other system stations have been converted into idle time slots by said station, and means responsive to a first predetermined value in said QR count for altering a request signal being transmitted over said second channel, wherein said request signal indicates a request for an idle time slot and wherein said altering means erases said request signal and changes the value in said QR count.
Claim 2
Dependent Claim 127 words
A station for use in a time division multiplex (TDM) communication system including a plurality of stations communicating over first and second unidirectional communication channels, said station having the capability of converting read time slots into idle time slots and comprising queue of request QR counter means for establishing a QR count indicating how many time slots over said first channel from other system stations have been converted into idle time slots by said station, and means responsive to a first predetermined value in said QR count for altering a request signal being transmitted over said second channel, wherein said request signal indicates a request for an idle time slot and wherein said altering means erases said request signal and changes the value in said QR count.
Claim 3
Dependent Claim 14 words
The station of claim 1 wherein said read slots are read by said station.
Claim 4
Dependent Claim 26 words
The station of claim 1 wherein said altering means erases said request signal and increments said QR counter when said QR count is less than zero.
Claim 5
Dependent Claim 33 words
The station of claim 3 wherein said altering means writes an additional request signal for transmission over said second channel and decrements said QR counter when said QR count is greater than zero.
Claim 6
Dependent Claim 42 words
The station of claim 3 wherein said altering means, in response to said QR count being equal to zero, does not alter a request signal being transmitted over said second channel and does not change the QR count of said QR counter.
Claim 7
Dependent Claim 89 words
The station of claim 3 further comprising request counter means for counting request signals on said second channel while said station is not in an active transmit mode, countdown counter means for counting each idle time slot on said first channel when said station is in an active transmit mode, means for transferring a request count from said request counter means to said countdown counter means when said station enters said active transmit mode, and means for incrementing said QR counter when said station enters said active transmit mode.
Claim 8
Dependent Claim 66 words
The station of claim 6 further comprising means for releasing a time slot addressed to said station, means responsive to a released time slot for comparing both the count of said countdown counter and said request counter means to zero, and means for decrementing said QR counter when said comparing means indicates that either said countdown count or said request count that is greater than zero.
Claim 9
Dependent Claim 32 words
The station of claim 7 further including bypass means for bypassing said decrementing means when said comparing means indicates that both said countdown count and said request count are equal to zero.
Claim 10
Dependent Claim 83 words
The station of claim 3 further comprising a second queue of request QR counter means for establishing a second QR count, which indicates how many idle time slots of said second channel have been released by said station and second altering means, responsive to a predetermined value in said second QR count, for altering a second request signal being transmitted over said first channel, wherein said second altering means erases said second request signal and changes the value in said second QR counter.
Claim 11
Dependent Claim 36 words
The station of claim 9 wherein second altering means writes an additional second request signal for transmission over said first channel and decrements said second QR counter when said second QR count is greater than zero.
Claim 12
Dependent Claim 167 words
A station for use in a time division multiplex (TDM) communication system including a plurality of stations communicating over first and second unidirectional communication channels, said station having the capability of converting read time slots into idle time slots and comprising queue of request QR counter means for establishing a QR count indicating how many time slots over said first channel from other system stations have been converted into an idle time slot by said station and when said station can transmit data over an idle time slot of said first channel, means for determining when said QR count is a first predetermined value or a second predetermined value, and means for altering a request signal being transmitted over said second channel, said altering means erasing said request signal when said determining means has determined that said QR count is said first predetermined value and said altering means writing said request signal when said determining means has determined that said QR count is said second predetermined value.
Claim 13
Dependent Claim 167 words
A station for use in a time division multiplex (TDM) communication system including a plurality of stations communicating over first and second unidirectional communication channels, said station having the capability of converting read time slots into idle time slots and comprising queue of request QR counter means for establishing a QR count indicating how many time slots over said first channel from other system stations have been converted into an idle time slot by said station and when said station can transmit data over an idle time slot of said first channel, means for determining when said QR count is a first predetermined value or a second predetermined value, and means for altering a request signal being transmitted over said second channel, said altering means erasing said request signal when said determining means has determined that said QR count is said first predetermined value and said altering means writing said request signal when said determining means has determined that said QR count is said second predetermined value.
Claim 14
Dependent Claim 49 words
The station of claim 11 wherein said altering means erases said request signal when said determining means has determined that said QR count is less that zero and said altering means writes said request signal when said determining means has determined that said QR count is greater than zero.
Claim 15
Dependent Claim 93 words
A station for use in a time division multiplex (TDM) communication system including first and second unidirectional communication channels, said station comprising means for receiving information over said first channel in a time slot addressed to said station and for erasing said information from said time slot and means responsive to the receiving and erasing by said receiving means for erasing a request signal being received over said second channel from another station, said request signal indicating to said station that a request exists for an empty time slot on said first channel.
Claim 16
Dependent Claim 93 words
A station for use in a time division multiplex (TDM) communication system including first and second unidirectional communication channels, said station comprising means for receiving information over said first channel in a time slot addressed to said station and for erasing said information from said time slot and means responsive to the receiving and erasing by said receiving means for erasing a request signal being received over said second channel from another station, said request signal indicating to said station that a request exists for an empty time slot on said first channel.
Claim 17
Dependent Claim 112 words
A time division multiplex (TDM) communication system comprising first and second unidirectional communication channels, at least two stations connected to said channels, each station arranged to receive and transmit information over either said first or second unidirectional channel, at least one station including means for receiving information over said first channel in a time slot addressed to said at least one station and for erasing said information from said time slot and means responsive to the receiving and erasing by said receiving means for erasing a request signal being received over said second channel from another station of said system indicating a request for an empty time slot on said first channel.
Claim 18
Dependent Claim 112 words
A time division multiplex (TDM) communication system comprising first and second unidirectional communication channels, at least two stations connected to said channels, each station arranged to receive and transmit information over either said first or second unidirectional channel, at least one station including means for receiving information over said first channel in a time slot addressed to said at least one station and for erasing said information from said time slot and means responsive to the receiving and erasing by said receiving means for erasing a request signal being received over said second channel from another station of said system indicating a request for an empty time slot on said first channel.
Claim 19
Dependent Claim 153 words
A time division multiplex (TDM) communication system comprising first and second unidirectional communication channels and a station connected to said channels and arranged to receive and transmit information over either said first or said second unidirectional channel, said station having the capability of converting read time slots into idle time slots and including queue of request QR counter means for establishing a QR count, indicating how many time slots over said first channel from other system stations have been converted into idle time slots by said station and when said station can transmit data over an idle time slot of said first channel, means responsive to said QR count, for altering a request signal being transmitted over said second channel, said request signal indicating a request for an idle time slot and, said altering means erasing said request signal and changing said QR count when said QR count is a first predetermined value.
Claim 20
Dependent Claim 153 words
A time division multiplex (TDM) communication system comprising first and second unidirectional communication channels and a station connected to said channels and arranged to receive and transmit information over either said first or said second unidirectional channel, said station having the capability of converting read time slots into idle time slots and including queue of request QR counter means for establishing a QR count, indicating how many time slots over said first channel from other system stations have been converted into idle time slots by said station and when said station can transmit data over an idle time slot of said first channel, means responsive to said QR count, for altering a request signal being transmitted over said second channel, said request signal indicating a request for an idle time slot and, said altering means erasing said request signal and changing said QR count when said QR count is a first predetermined value.
Claim 21
Dependent Claim 15 words
The station of claim 15 wherein said read time slots are read by said station.
Claim 22
Dependent Claim 26 words
The system of claim 15 wherein said altering means erases said request signal and increments said QR counter when said QR counter is less than zero.
Claim 23
Dependent Claim 35 words
The system of claim 17 wherein at station said altering means writes an additional request signal for transmission over said second channel and decrements said QR counter when said QR count is greater than zero.
Claim 24
Independent Claim 108 words
A method of operating a station for use in a time division multiplex (TDM) communication system having a plurality of stations communicating over first and second unidirectional communication channels, at least one station having the capability of converting read time slots into idle time slots, said method comprising the steps of: establishing a queue of request QR count which indicates how many time slots over said first channel from other system stations have been converted into an idle time slot by an individual station and altering a request signal being transmitted over said second channel by erasing said request signal and changing the value in said QR count.
Claim 25
Independent Claim 108 words
A method of operating a station for use in a time division multiplex (TDM) communication system having a plurality of stations communicating over first and second unidirectional communication channels, at least one station having the capability of converting read time slots into idle time slots, said method comprising the steps of: establishing a queue of request QR count which indicates how many time slots over said first channel from other system stations have been converted into an idle time slot by an individual station and altering a request signal being transmitted over said second channel by erasing said request signal and changing the value in said QR count.
Claim 26
Dependent Claim 26 words
The method of claim 19 wherein said altering step erases said request signal and increments said QR counter when said QR count is less than zero.
Claim 27
Dependent Claim 33 words
The method of claim 20 wherein said altering step writes an additional request signal for transmission over said second channel and decrements said QR counter when said QR count is greater than zero.
Claim 28
Independent Claim 98 words
A method of operating a station for use in a time division multiplex (TDM) communication system including a plurality of stations communicating over first and second unidirectional communication channels, said method comprising the steps of receiving information over said first channel in a time slot addressed to said station and for erasing said information from said time slot and in response to said receiving step erasing a request signal being received over said second channel; from another station, said request signal indicating to said station that a request exists for an empty time slot on said first channel.
Claim 29
Independent Claim 98 words
A method of operating a station for use in a time division multiplex (TDM) communication system including a plurality of stations communicating over first and second unidirectional communication channels, said method comprising the steps of receiving information over said first channel in a time slot addressed to said station and for erasing said information from said time slot and in response to said receiving step erasing a request signal being received over said second channel; from another station, said request signal indicating to said station that a request exists for an empty time slot on said first channel.
Claim 30
Independent Claim 133 words
A method of operating a time division multiplex (TDM) communication system including first and second unidirectional communication channels and at least two stations connected to said channels, each station arranged to receive and transmit information over either said first or said second unidirectional channel, at least one station having the capability of converting read time slots into idle time slots, said method comprising the steps of: at least one station, establishing a queue of request QR count which indicates how many time slots over said first channel from other system stations have been converted into an idle time slot by an erasure station and altering a request signal being transmitted over said second channel by erasing said request signal and changing said QR count when said QR count is a first predetermined value.
Claim 31
Independent Claim 133 words
A method of operating a time division multiplex (TDM) communication system including first and second unidirectional communication channels and at least two stations connected to said channels, each station arranged to receive and transmit information over either said first or said second unidirectional channel, at least one station having the capability of converting read time slots into idle time slots, said method comprising the steps of: at least one station, establishing a queue of request QR count which indicates how many time slots over said first channel from other system stations have been converted into an idle time slot by an erasure station and altering a request signal being transmitted over said second channel by erasing said request signal and changing said QR count when said QR count is a first predetermined value.
Claim 32
Dependent Claim 26 words
The method of claim 23 wherein said altering step erases said request signal and increments said QR counter when said QR count is less than zero.

References Cited (Backward Citations)

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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) 1996-05-24 1996-11-23 1997-05-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-05-24 2000-11-23 2001-05-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-05-24 2004-11-23 2005-05-25 $7700.00 Window Closed / Lapsed

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