Dual carrier modulation precoding
A method (300) for performing dual carrier modulation (DCM) precoding. The method comprises generating data sub-blocks (S320), independently interleaving the sub-blocks (S330), generating bit vectors by grouping bits of the interleaved sub-blocks (S350), mapping the bit vectors into data symbols (S360), and precoding the data symbols using a precoding matrix to generate precoded symbols (S370).
1. A method for performing dual carrier modulation (DCM) precoding using an orthogonal frequency division multiplexing (OFDM) transmitter, comprising:
generating, by the OFDM transmitter, data sub-blocks;
independently interleaving the sub-blocks;
generating bit vectors by grouping bits of the interleaved sub-blocks;
mapping the bit vectors into data symbols; and
precoding the data symbols using a precoding matrix to generate precoded symbols, the precoding matrix being a unitary matrix and a real matrix that includes only integer elements multiplied by a real normalization factor, the precoding matrix for a 16QAM modulation scheme being selected from the group consisting of:
R
1
=
1
29
[
5
2
2
-
5
]
;
R
2
=
1
34
[
5
3
3
-
5
]
;
R
3
=
1
58
[
7
3
3
-
7
]
;
R
4
=
1
73
[
8
3
3
-
8
]
;
R
5
=
1
305
[
16
7
7
-
16
]
;
R
6
=
1
65
[
7
4
4
-
7
]
;
and
R
7
=
1
337
[
16
9
9
-
16
]
.
2. The method of claim 1 , further comprising:
interleaving the precoded symbols by distributing the precoded symbols to different data subcarriers of a plurality of OFDM symbols; and
modulating the precoded symbols into the data subcarriers of the plurality of OFDM symbols.
3. The method of claim 1 , wherein generating the data sub-blocks further comprises grouping encoded input information bits into data blocks, wherein the number of bits in each data block is a function of a modulation scheme and a transfer rate; and dividing the data blocks into the plurality of sub-blocks.
4. The method of claim 3 , wherein the modulation scheme is at least 16QAM.
5. The method of claim 1 , wherein generating the bit vectors further comprises grouping bits of the interleaved sub-blocks into a plurality of bit groups and combining the respective bit group of the interleaved sub-blocks to generate the bit vectors.
6. The method of claim 1 , wherein the mapping of the bit vectors into the data symbols is performed using at least one of a Gray mapping or a set-partitioning mapping.
7. A non-transitory computer-readable medium having stored thereon computer executable code for performing dual carrier modulation (DCM) precoding, comprising:
generating data sub-blocks;
independently interleaving the generated sub-blocks;
generating bit vectors by grouping bits of the interleaved sub-blocks;
mapping the bit vectors into data symbols; and
precoding the data symbols using a precoding matrix to generate precoded symbols, the precoding matrix being a unitary matrix and a real matrix that includes only integer elements multiplied by a real normalization factor, the precoding matrix for a 16QAM modulation scheme being selected from the group consisting of:
R
1
=
1
29
[
5
2
2
-
5
]
;
R
2
=
1
34
[
5
3
3
-
5
]
;
R
3
=
1
58
[
7
3
3
-
7
]
;
R
4
=
1
73
[
8
3
3
-
8
]
;
R
5
=
1
305
[
16
7
7
-
16
]
;
R
6
=
1
65
[
7
4
4
-
7
]
;
and
R
7
=
1
337
[
16
9
9
-
16
]
.
8. An orthogonal frequency division multiplexing (OFDM) transmitter for performing a dual carrier modulation (DCM) precoding, comprising:
a bit interleaver for independently interleaving sub-blocks including encoded input information bits;
a constellation mapping unit for generating bit vectors from the interleaved sub-blocks and mapping the bit vectors to information symbols, wherein the constellation mapping unit is further capable of precoding the information symbols using a precoding matrix to generate precoded information symbols, the precoding matrix being a unitary matrix and a real matrix that includes only integer elements multiplied by a real normalization factor, the precoding matrix for a 16QAM modulation scheme being selected from the group consisting of:
R
1
=
1
29
[
5
2
2
-
5
]
;
R
2
=
1
34
[
5
3
3
-
5
]
;
R
3
=
1
58
[
7
3
3
-
7
]
;
R
4
=
1
73
[
8
3
3
-
8
]
;
R
5
=
1
305
[
16
7
7
-
16
]
;
R
6
=
1
65
[
7
4
4
-
7
]
;
and
R
7
=
1
337
[
16
9
9
-
16
]
;
and
a symbol interleaver for distributing the precoded information symbols into different data subcarriers of a plurality of OFDM symbols.
9. The OFDM transmitter of claim 8 , further comprising:
an encoder for encoding the input information bits; and
a puncturer for generating the sub-blocks from the encoded input information bits.