Method and apparatus for resource mapping and code division multiplexing
The present disclosure discloses a method and an apparatus for resource mapping and code division multiplexing. In the present disclosure, each cell selects a mapping scheme among at least two mapping schemes to implement resource mapping, which effectively reduces interference imposed on reference signal symbols of users at the edge of a cell; vector switching is performed for an orthogonal matrix to obtain multiple different codeword sequences and implement codeword design, so that a problem that the output power of reference signal symbols is unbalanced can be effectively alleviated.
1. A code division multiplexing method in a wireless telecommunication system, comprising:
performing vector switching for a selected orthogonal matrix to obtain multiple different codeword sequences;
determining mapping relations between the multiple different codeword sequences and each reference signal sub-carrier; and
multiplexing, on each reference signal sub-carrier, reference signal symbols of each space layer according to a codeword sequence that is corresponding to each reference signal sub-carrier.
2. The method according to claim 1 , wherein performing vector switching for a selected orthogonal matrix to obtain multiple different codeword sequences comprises:
performing column vector switching for a 4-dimensional orthogonal matrix W to obtain 4 different codeword sequences, wherein:
W(:,m) represents a column vector corresponding to column m of the orthogonal matrix W, m ranges from 1 to 4, and A=W(:,1), B=W(:,2), C=W(:,3), and D=W(:,4);
the 4 different codeword sequences are:
W 1 =[A,B,C,D];
W 2 =[B,A,D,C];
W 3 =[C,D,A,B ] or [ C,D,B,A];
W 4 =[D,C,B,A ] or [ D,C,A,B];
wherein determining mapping relations between the multiple different codeword sequences and each reference signal sub-carrier comprises:
determining that the 4 different codeword sequences W 1 , W 2 , W 3 , and W 4 are adopted by each reference signal sub-carrier by turns.
3. The method according to claim 1 , wherein performing vector switching for a selected orthogonal matrix to obtain multiple different codeword sequences comprises:
performing row vector switching for a 4-dimensional orthogonal matrix W to obtain 4 different codeword sequences, wherein:
W′(m,:) represents a row vector corresponding to row m of the orthogonal matrix W, m ranges from 1 to 4, A′=W′(1,:), B′=W′(2,:), C′=W′(3,:), D′=W′(4,:);
the 4 different codeword sequences are:
W
1
‵
=
[
A
‵
B
‵
C
‵
D
‵
]
;
W
2
‵
=
[
B
‵
A
‵
D
‵
C
‵
]
;
W
3
‵
=
[
C
‵
D
‵
A
‵
B
‵
]
or
[
C
‵
D
‵
B
‵
A
‵
]
;
W
4
‵
=
[
D
‵
C
‵
B
‵
A
‵
]
or
[
D
‵
C
‵
A
‵
B
‵
]
;
and
wherein determining mapping relations between the multiple different codeword sequences and each reference signal sub-carrier comprises:
determining that the 4 different codeword sequences W 1 ′, W 2 ′, W 3 ′ and W 4 ′ are adopted by each reference signal sub-carrier by turns.
4. A codeword design apparatus in a wireless telecommunication system, comprising:
an obtaining unit, configured to perform vector switching for a selected orthogonal matrix to obtain multiple different codeword sequences;
a determining unit, configured to determine mapping relations between the multiple different codeword sequences obtained by the obtaining unit and each reference signal sub-carrier; and
a multiplexing unit, configured to multiplex, on each reference signal sub-carrier, reference signal symbols of each space layer according to a codeword sequence that is corresponding to each reference signal sub-carrier.
5. The apparatus according to claim 4 , wherein:
the obtaining unit is configured to perform column vector switching for a 4-dimensional orthogonal matrix W to obtain 4 different codeword sequences, wherein
W(:,m) represents a column vector corresponding to column m of the orthogonal matrix W, m ranges from 1 to 4, A=W(:,1), B=W(:,2), C=W(:,3), and D=W(:,4);
the 4 different codeword sequences are:
W 1 =[A,B,C,D];
W 2 =[B,A,D,C];
W 3 =[C,D,A,B ] or [ C,D,B,A];
W 4 =[D,C,B,A ] or [ D,C,A,B]; and
the determining unit is configured to determine that the 4 different codeword sequences W 1 , W 2 , W 3 , and W 4 are adopted by each reference signal sub-carrier by turns.
6. The apparatus according to claim 4 , wherein:
the obtaining unit is configured to perform row vector switching for a 4-dimensional orthogonal matrix W to obtain 4 different codeword sequences, wherein:
W′(m,:) represents a row vector corresponding to row m of the orthogonal matrix W, m ranges from 1 to 4, A′=W′(1,:), B′=W′(2,:), C′=W′(3,:), and D′=W′(4,:);
the 4 different codeword sequences are:
W
1
‵
=
[
A
‵
B
‵
C
‵
D
‵
]
;
W
2
‵
=
[
B
‵
A
‵
D
‵
C
‵
]
;
W
3
‵
=
[
C
‵
D
‵
A
‵
B
‵
]
or
[
C
‵
D
‵
B
‵
A
‵
]
;
W
4
‵
=
[
D
‵
C
‵
B
‵
A
‵
]
or
[
D
‵
C
‵
A
‵
B
‵
]
;
and
the determining unit is configured to determine that the 4 different codeword sequences W 1 ′, W 2 ′, W 3 ′ and W 4 ′ are adopted by each reference signal sub-carrier by turns.
7. A codeword design apparatus in a wireless telecommunication system, comprising:
a processor, configured to perform vector switching for a selected orthogonal matrix to obtain multiple different codeword sequences, determine mapping relations between the multiple different codeword sequences and each reference signal sub-carrier, and multiplex, on each reference signal sub-carrier, reference signal symbols of each space layer according to a codeword sequence that is corresponding to each reference signal sub-carrier; and
a transmitter, configured to transmit the reference signal symbols.
8. The apparatus according to claim 7 , wherein the processor is further configured to:
perform column vector switching for a 4-dimensional orthogonal matrix W to obtain 4 different codeword sequences, wherein
W(:,m) represents a column vector corresponding to column m of the orthogonal matrix W, m ranges from 1 to 4, A=W(:,1), B=W(:,2), C=W(:,3), and D=W(:,4);
the 4 different codeword sequences are:
W 1 =[A,B,C,D];
W 2 =[B,A,D,C];
W 3 =[C,D,A,B ] or [ C,D,B,A];
W 4 =[D,C,B,A ] or [ D,C,A,B];
and wherein the processor is further configured to:
determine that the 4 different codeword sequences W 1 , W 2 , W 3 , and W 4 are adopted by each reference signal sub-carrier by turns.
9. The apparatus according to claim 7 , wherein the processor is further configured to:
perform row vector switching for a 4-dimensional orthogonal matrix W to obtain 4 different codeword sequences, wherein:
W′(m,:) represents a row vector corresponding to row m of the orthogonal matrix W, m ranges from 1 to 4, A′=W(1,:), B′=W′(2,:), C′=W′(3,:), and D′=W′(4,:);
the 4 different codeword sequences are:
W
1
‵
=
[
A
‵
B
‵
C
‵
D
‵
]
;
W
2
‵
=
[
B
‵
A
‵
D
‵
C
‵
]
;
W
3
‵
=
[
C
‵
D
‵
A
‵
B
‵
]
or
[
C
‵
D
‵
B
‵
A
‵
]
;
W
4
‵
=
[
D
‵
C
‵
B
‵
A
‵
]
or
[
D
‵
C
‵
A
‵
B
‵
]
;
and wherein the processor is further configured to:
determine that the 4 different codeword sequences W 1 ′, W 2 ′, W 3 ′ and W 4 ′ are adopted by each reference signal sub-carrier by turns.