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US5301209A Expired / Lapsed US ⏱️ 0.0 years remaining

Multidimensional trellis-coded modulation for fading channels

Assignee: Nokia Bell Labs
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Filing: 1991-10-09
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Granted: 1994-04-05
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Expires: 2011-10-09
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Abstract

Abstract The decoding depth of a multidimensional trellis-coding scheme with X-fold time diversity is reduced, or minimized. As a result, an improvement in error rate performance is achieved for the multidimensional trellis code, which can then be favorably applied to a fading channel application.

Inventors

  • 👤 Lee-Fang Wei

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 18:41
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/18; H04L27/186

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 199 words
A method comprising receiving a stream of input data comprising an average of m data bits every T signaling interval, where m>0 and T>0, using a trellis-encoder to encode the stream of input data into one of a plurality of sequences of 2N-dimensional signal points, where N>1, said 2N-dimensional signal points being taken from a 2N-dimensional constellation, said trellis-encoder having an X-fold time diversity, where X>1, and transmitting the sequence of 2N-dimensional signal points, said constellation comprising a first and a second family, each family comprising a number of subsets, each subset comprising at least one 2N-dimensional signal point, said trellis-encoder comprising a number of states, each state having a plurality of state transitions, said plurality of state transitions being assigned subsets of the same family, where those states with state transitions assigned subsets of the first family are included in a first set and those states with state transitions assigned subsets of the second family are included in a second set, and where those state transitions between a present state and a plurality of next states, said next states being in the same set of states, are assigned subsets which maximize the minimum time diversity between those subsets.
Claim 2
Independent Claim 199 words
A method comprising receiving a stream of input data comprising an average of m data bits every T signaling interval, where m>0 and T>0, using a trellis-encoder to encode the stream of input data into one of a plurality of sequences of 2N-dimensional signal points, where N>1, said 2N-dimensional signal points being taken from a 2N-dimensional constellation, said trellis-encoder having an X-fold time diversity, where X>1, and transmitting the sequence of 2N-dimensional signal points, said constellation comprising a first and a second family, each family comprising a number of subsets, each subset comprising at least one 2N-dimensional signal point, said trellis-encoder comprising a number of states, each state having a plurality of state transitions, said plurality of state transitions being assigned subsets of the same family, where those states with state transitions assigned subsets of the first family are included in a first set and those states with state transitions assigned subsets of the second family are included in a second set, and where those state transitions between a present state and a plurality of next states, said next states being in the same set of states, are assigned subsets which maximize the minimum time diversity between those subsets.
Claim 3
Dependent Claim 34 words
The method of claim 1 wherein the assignment of subsets to state transitions from the present state to the plurality of next states of the same set further maximizes the minimum square product distance.
Claim 4
Dependent Claim 21 words
The method of claim 1 further comprising the step of interleaving the sequence of 2N-dimensional signal points before the transmitting step.
Claim 5
Dependent Claim 60 words
The method of claim 1 wherein the step of using the trellis encoder includes the steps of providing a stream of output data comprising an average of m+r data bits every T signaling interval, where r>0, and mapping the stream of output data in each group of N signaling intervals to one of the 2N-dimensional signal points from said constellation.
Claim 6
Dependent Claim 24 words
The method of claim 1 wherein the intra-subset minimum time diversity and intra-subset minimum square product distance in each of said family is maximized.
Claim 7
Dependent Claim 22 words
The method of claim 1 wherein said trellis-encoder is a 4 state trellis code, and said 2N-dimensional constellation is a 4D constellation.
Claim 8
Dependent Claim 44 words
The method of claim 6 wherein said method has a first minimum decoding depth (MDD1) equal to 1, a second minimum decoding depth (MDD2) equal to 3, a third minimum decoding depth (MDD3) equal to 5 and a minimum time diversity equal to 2.
Claim 9
Dependent Claim 14 words
The method of claim 6 wherein said 4D constellation comprises a 2D 8-PSK constellation.
Claim 10
Dependent Claim 14 words
The method of claim 6 wherein said 4D constellation comprises a 2D 6-PSK constellation.
Claim 11
Dependent Claim 204 words
Apparatus comprising means for receiving a stream of input data comprising an average of m data bits every T signaling interval, where m>0 and T>0, means for trellis-encoding the stream of input data into one of a plurality of sequences of 2N-dimensional signal points, where N>1, said 2N-dimensional signal points being taken from a 2N-dimensional constellation, said means for trellis-encoding having an X-fold time diversity, where X>1, and means for transmitting the sequence of 2N-dimensional signal points, said constellation comprising a first and a second family, each family comprising a number of subsets, each subset comprising at least one 2N-dimensional signal point, said means for trellis-encoding comprising a number of states, each state having a plurality of state transitions, said plurality of state transitions being assigned subsets of the same family, where those states with state transitions assigned subsets of the first family are included in a first set and those states with state transitions assigned subsets of the second family are included in a second set, and where those state transitions between a present state and a plurality of next states, said next states being in the same set of states, are assigned subsets which maximize the minimum time diversity between those subsets.
Claim 12
Dependent Claim 204 words
Apparatus comprising means for receiving a stream of input data comprising an average of m data bits every T signaling interval, where m>0 and T>0, means for trellis-encoding the stream of input data into one of a plurality of sequences of 2N-dimensional signal points, where N>1, said 2N-dimensional signal points being taken from a 2N-dimensional constellation, said means for trellis-encoding having an X-fold time diversity, where X>1, and means for transmitting the sequence of 2N-dimensional signal points, said constellation comprising a first and a second family, each family comprising a number of subsets, each subset comprising at least one 2N-dimensional signal point, said means for trellis-encoding comprising a number of states, each state having a plurality of state transitions, said plurality of state transitions being assigned subsets of the same family, where those states with state transitions assigned subsets of the first family are included in a first set and those states with state transitions assigned subsets of the second family are included in a second set, and where those state transitions between a present state and a plurality of next states, said next states being in the same set of states, are assigned subsets which maximize the minimum time diversity between those subsets.
Claim 13
Dependent Claim 34 words
The apparatus of claim 10 wherein the assignment of subsets to state transitions from the present state to the plurality of next states of the same set further maximizes the minimum square product distance.
Claim 14
Dependent Claim 24 words
The apparatus of claim 10 further comprising a means for interleaving the sequence of 2N-dimensional signal points before input to the means for transmitting.
Claim 15
Dependent Claim 58 words
The apparatus of claim 10 wherein the means for trellis-encoding includes means for providing a stream of output data comprising an average of m+r data bits every T signaling interval, where r>0, and means for mapping the stream of output data in each group of N signaling intervals to one of the 2N-dimensional signal points from said constellation.
Claim 16
Dependent Claim 24 words
The apparatus of claim 10 wherein the intra-subset minimum time diversity and intra-subset minimum square product distance in each of said family is maximized.
Claim 17
Dependent Claim 24 words
The apparatus of claim 10 wherein said means for trellis-encoding uses a 4 state trellis code, and said 2N-dimensional constellation is a 4D constellation.
Claim 18
Dependent Claim 45 words
The apparatus of claim 15 wherein said apparatus has a first minimum decoding depth (MDD1) equal to 1, a second minimum decoding depth (MDD2) equal to 3, an a third minimum decoding depth (MDD3) equal to 5, and a minimum time diversity equal to 2.
Claim 19
Dependent Claim 14 words
The apparatus of claim 15 wherein said 4D constellation comprises a 2D 8-PSK constellation.
Claim 20
Dependent Claim 14 words
The apparatus of claim 15 wherein said 4D constellation comprises a 2D 6-PSK constellation.

References Cited (Backward Citations)

US4945549A Cited
US4980897A Cited
US5029185A Cited
US5056112A Cited
US5048057A Cited
US5088113A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1997-04-04 1997-10-04 1998-04-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2001-04-04 2001-10-04 2002-04-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2005-04-04 2005-10-04 2006-04-05 $7700.00 Window Closed / Lapsed

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