System and method performing quadrature amplitude modulation by combining co-sets and strongly coded co-set identifiers
First Claim
1. A method of encoding a stream of data elements comprising:
- splitting the stream of data elements into a first stream and a second stream;
encoding the first stream using symbol-based Turbo-encoding to produce a first encoded stream;
performing a constellation mapping using a combination of the first encoded stream and a third stream which is based on the second stream;
encoding the second stream to produce the third stream using relatively weak encoding compared to that used in encoding the first stream, the method further comprising;
defining a signal constellation comprising a plurality of constellation points;
defining a plurality of co-sets within the plurality of constellation points such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation;
performing said constellation mapping by using the first encoded stream to identify a sequence of co-sets of said plurality of co-sets, and by using the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream.
4 Assignments
0 Petitions
Accused Products
Abstract
A method of encoding a stream of data elements is provided which involves splitting the stream of data elements into a first stream and a second stream; encoding the first stream to produce a first encoded stream; performing a constellation mapping using a combination of the first encoded stream and a third stream which is based an the second stream. This may involve defining a signal constellation; defining a plurality of co-sets within the constellation such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; performing said constellation mapping by using the first encoded stream to identify a sequence of co-sets of said plurality of co-sets, and by using the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream.
42 Citations
32 Claims
-
1. A method of encoding a stream of data elements comprising:
-
splitting the stream of data elements into a first stream and a second stream; encoding the first stream using symbol-based Turbo-encoding to produce a first encoded stream; performing a constellation mapping using a combination of the first encoded stream and a third stream which is based on the second stream; encoding the second stream to produce the third stream using relatively weak encoding compared to that used in encoding the first stream, the method further comprising; defining a signal constellation comprising a plurality of constellation points; defining a plurality of co-sets within the plurality of constellation points such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; performing said constellation mapping by using the first encoded stream to identify a sequence of co-sets of said plurality of co-sets, and by using the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A transmitter comprising:
-
a de-multiplexer adapted to split an input stream into a first stream and a second stream; a first encoder adapted to encode the first stream using symbol-based Turbo-encoding to produce a first encoded stream; a second encoder adapted to encode a second stream to produce a third stream using relatively weak encoding compared to that used in the first encoder; a constellation mapper adapted to perform constellation mapping using a combination of the first encoded stream and the third stream which is based on the second stream, wherein; the constellation mapper is adapted to map to a signal constellation comprising a plurality of constellation points within which is defined a plurality of co-sets such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; the constellation mapper is adapted to use the first encoded stream to identify a sequence of co-sets of said plurality of co-sets; and the constellation mapper is adapted to use the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream. - View Dependent Claims (12, 13, 14, 15, 16, 17)
-
-
18. A method of encoding a stream of data elements comprising:
-
splitting the stream of data elements into a first stream and a second stream; encoding the first stream using Turbo-encoding to produce a first encoded stream; performing a constellation mapping using a combination of the first encoded stream and a third stream which is based on the second stream; encoding the second stream to produce the third stream using relatively weak encoding compared to that used in encoding the first stream, the method further comprising; defining a signal constellation comprising a plurality of constellation points; defining a plurality of co-sets within the plurality of constellation points such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; performing said constellation mapping by using the first encoded stream to identify a sequence of co-sets of said plurality of co-sets, and by using the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27)
-
-
28. A transmitter comprising:
-
a de-multiplexer adapted to split an input stream into a first stream and a second stream; a first encoder adapted to encode the first stream using Turbo-encoding to produce a first encoded stream; a second encoder adapted to encode a second stream to produce a third stream using relatively weak encoding compared to that used in the first encoder; a constellation mapper adapted to perform constellation mapping using a combination of the first encoded stream and the third stream which is based on the second stream, wherein; the constellation mapper is adapted to map to a signal constellation comprising a plurality of constellation points within which is defined a plurality of co-sets such that a minimum distance between constellation points within each co-set is larger than a minimum distance between any constellation points within the signal constellation; the constellation mapper is adapted to use the first encoded stream to identify a sequence of co-sets of said plurality of co-sets; and the constellation mapper is adapted to use the third stream to identify a sequence of constellation points within respective co-sets of the sequence of co-sets identified by said first encoded stream. - View Dependent Claims (29, 30, 31)
-
-
32. A method of encoding a stream of data elements comprising:
-
splitting the stream of data elements into a first stream and a second stream; encoding the first stream using symbol-based Turbo-encoding to produce a first encoded stream; performing a constellation mapping using a combination of the first encoded stream and a third stream which is based on the second stream; encoding the second stream to produce the third stream using relatively weak encoding compared to that used in encoding the first stream, the method further comprising; performing shaping and said second encoding on the second stream to produce the third stream; wherein performing constellation shaping for a given signal constellation comprising a plurality of constellation points comprises; associating a cost with each of the plurality of constellation points; defining a hierarchy of blocks, the hierarchy having a plurality of layers comprising at least a first layer and a last layer, each layer having fewer blocks than each previous layer; wherein the first layer is formed by ordering all of the constellation points according to cost, and then assigning a first lowest cost group of constellation points to a first shaping partition, a second lowest cost group of constellation points to a second shaping partition, and so on until a highest cost group of constellation points assigned to a last shaping partition, each shaping partition being assigned a cost based on the costs of the constellation points in the shaping partition, each shaping partition being a first layer block; wherein an element in each other layer is formed by combining two blocks of a previous layer and is assigned a cost based on the costs of the two blocks of the previous layer, a block of each layer being comprised of one of the elements according to cost, or a group of the elements according to cost; the last layer having a single block comprising a plurality of elements; shaping gain being achieved by only mapping to a subset of the elements of the last layer.
-
Specification