Method and apparatus for multiple input multiple output (MIMO) transmit beamforming
A wireless communications network is provided. The wireless communications network comprises a plurality of base stations. Each one of said base stations is capable of wireless communications with a plurality of subscriber stations. At least one of said plurality of base stations comprises a processor configured to select a codeword from a codebook and precode data with the selected codeword, and a transmitter configured to transmit the precoded data. Rank 1 of the codebook is selected from the following algorithm: Codebook Matrix Index (CMI) Base Matrix Rank 1 1 V8(:, :, 3) V8(:, 1, 3) 2 V8(:, 2, 3) 3 V8(:, 3, 3) 4 V8(:, 4, 3) 5 V8(:, 5, 3) 6 V8(:, 6, 3) 7 V8(:, 7, 3) 8 V8(:, 8, 3) 9 V8(:, 9, 3) 10 V8(:, 10, 3) 11 V8(:, 11, 3) 12 V8(:, 12, 3) 13 V8(:, 13, 3) 14 V8(:, 14, 3) 15 V8(:, 15, 3) 16 V8(:, 16, 3).
1. A base station including a multiple antenna array for wireless communication, comprising:
a codebook;
a processor configured to select a codeword from the codebook and to code data with the selected codeword; and
a transmitter configured to transmit the coded data,
wherein codewords in the codebook are based on values shown in the following table:
V8(:, CMI, 3) = [c1, c2, . . . c8];
CMI
c1
c2
c3
c4
c5
c6
c7
c8
1
0.3536
−0.3051 −
0.1732 +
0.0062 −
−0.1839 +
0.3112 −
−0.3533 −
0.2987 +
0.1786i
0.3082i
0.3535i
0.3020i
0.1677i
0.0124i
0.1892i
2
0.3536
−0.2514 −
0.0041 +
0.2456 −
−0.3535 +
0.2571 +
−0.0123 −
−0.2397 +
0.2486i
0.3535i
0.2543i
0.0082i
0.2427i
0.3533i
0.2599i
3
0.3536
−0.1697 −
−0.1907 +
0.3527 +
−0.1479 −
−0.2107 +
0.3502 +
−0.1254 −
0.3102i
0.2977i
0.0244i
0.3211i
0.2839i
0.0486i
0.3306i
4
0.3536
−0.0614 −
−0.3322 +
0.1768 +
0.2708 −
−0.2709 −
−0.1767 +
0.3323 +
0.3482i
0.1210i
0.3062i
0.2273i
0.2272i
0.3062i
0.1208i
5
0.3536
0.0638 −
−0.3306 −
−0.1830 +
0.2646 +
0.2784 −
−0.1642 −
−0.3376 +
0.3478i
0.1254i
0.3025i
0.2345i
0.2180i
0.3131i
0.1050i
6
0.3536
0.1881 −
−0.1534 −
−0.3513 −
−0.2204 +
0.1168 +
0.3447 +
0.2499 −
0.2994i
0.3185i
0.0395i
0.2764i
0.3337i
0.0786i
0.2501i
7
0.3536
0.2892 −
0.1196 −
−0.0936 −
−0.2727 −
−0.3525 −
−0.3040 +
−0.1449 +
0.2034i
0.3327i
0.3409i
0.2251i
0.0272i
0.1805i
0.3225i
8
0.3536
0.3461 −
0.3241 −
0.2885 −
0.2407 −
0.1828 −
0.1172 −
0.0467 −
0.0721i
0.1412i
0.2044i
0.2590i
0.3026i
0.3336i
0.3505i
9
0.3536
0.3461 +
0.3241 +
0.2885 +
0.2407 +
0.1828 +
0.1172 +
0.0467 −
0.0721i
0.1412i
0.2044i
0.2590i
0.3026i
0.3336i
0.3505i
10
0.3536
0.2892 +
0.1196 +
−0.0936 +
−0.2727 +
−0.3525 +
−0.3040 −
−0.1449 −
0.2034i
0.3327i
0.3409i
0.2251i
0.0272i
0.1805i
0.3225i
11
0.3536
0.1881 +
−0.1534 +
−0.513 +
−0.2204 −
0.1168 −
0.3447 −
0.2499 +
0.2994i
0.3185i
0.0395i
0.2764i
0.3337i
0.0786i
0.2501i
12
0.3536
0.0638 +
−0.3306 +
−0.1830 −
0.2646 −
0.2784 +
−0.1642 +
−0.3376 −
0.3478i
0.1254i
0.3025i
0.2345i
0.2180i
0.3131i
0.1050i
13
0.3536
−0.0614 +
−0.3322 −
0.1768 −
0.2708 +
−0.2709 +
−0.1767 −
0.3323 −
0.3482i
0.1210i
0.3062i
0.2273i
0.2272i
0.3062i
0.1208i
14
0.3536
−0.1697 +
−0.1907 −
0.3527 −
−0.1479 +
−0.2107 −
0.3502 −
−0.1254 +
0.3102i
0.2977i
0.0244i
0.3211i
0.2839i
0.0486i
0.3306i
15
0.3536
−0.2514 +
0.0041 −
0.2456 +
−0.3535 −
0.2571 −
−0.0123 +
−0.2397 −
0.2486i
0.3535i
0.2543i
0.0082i
0.2427i
0.3533i
0.2599i
16
0.3536
−0.3051 +
0.1732 −
0.0062 +
−0.1839 −
0.3112 +
−0.3533 +
0.2987 −
0.1786i
0.3082i
0.3535i
0.3020i
0.1677i
0.0124i
0.1892i
where each row represents a Codebook Matrix Index (CMI) and each column (c1˜c8) represents an antenna in the multiple antenna array.
2. The base station of claim 1 , wherein the values in the table are obtained based on the following equation:
V
8
(
:
,
k
,
3
)
=
1
8
[
1
ⅇ
jπ
sin
(
θ
k
)
ⅇ
j2π
sin
(
θ
k
)
ⅇ
j3π
sin
(
θ
k
)
ⅇ
j4π
sin
(
θ
k
)
ⅇ
j5π
sin
(
θ
k
)
ⅇ
j6π
sin
(
θ
k
)
ⅇ
j7π
sin
(
θ
k
)
]
,
where θ k represents an angle of a beam, k=1, 2, 3, . . . 16 and k represents the CMI.
3. The base station of claim 2 , wherein θ k is given by the following equation:
θ
k
=
(
(
k
-
1
)
+
1
/
2
)
*
π
24
-
π
3
,
where k=1, 2, 3, . . . , 16, and k represents the CMI.
4. The base station of claim 1 , wherein the codebook is a 4-bit codebook.
5. The base station of claim 1 , wherein the table includes real and imaginary values for the second to eighth antennas (c2˜c8) of the multiple antenna array for each CMI.
6. A base station including a multiple antenna array for wireless communication, comprising:
a codebook;
a processor configured to select a codeword from the codebook and to code data with the selected codeword; and
a transmitter configured to transmit the coded data,
wherein codewords in the codebook are based on the following equation:
V
8
(
:
,
k
,
3
)
=
1
8
[
1
ⅇ
jπ
sin
(
θ
k
)
ⅇ
j2π
sin
(
θ
k
)
ⅇ
j3π
sin
(
θ
k
)
ⅇ
j4π
sin
(
θ
k
)
ⅇ
j5π
sin
(
θ
k
)
ⅇ
j6π
sin
(
θ
k
)
ⅇ
j7π
sin
(
θ
k
)
]
,
where θ k represents an angle of a beam and k=1, 2, 3, . . . , 16.
7. The base station of claim 6 , wherein θ k is given by the following equation:
θ
k
=
(
(
k
-
1
)
+
1
/
2
)
*
π
24
-
π
3
,
where k=1, 2, 3, . . . , 16.
8. The base station of claim 6 , wherein the codebook is a 4-bit codebook.
9. The base station of claim 6 , wherein the codewords in the codebook account for real and imaginary components of one or more antennas of the multiple antenna array.
10. A method for coding data in a base station including a multiple antenna array for wireless communication, the method comprising:
selecting a codeword from a codebook;
coding data with the selected codeword; and
transmitting the coded data,
wherein codewords in the codebook are based on values shown in the following table:
V8(:, CMI, 3) = [c1, c2, . . . c8];
CMI
c1
c2
c3
c4
c5
c6
c7
c8
1
0.3536
−0.3051 −
0.1732 +
0.0062 −
−0.1839 +
0.3112 −
−0.3533 −
0.2987 +
0.1786i
0.3082i
0.3535i
0.3020i
0.1677i
0.0124i
0.1892i
2
0.3536
−0.2514 −
0.0041 +
0.2456 −
−0.3535 +
0.2571 +
−0.0123 −
−0.2397 +
0.2486i
0.3535i
0.2543i
0.0082i
0.2427i
0.3533i
0.2599i
3
0.3536
−0.1697 −
−0.1907 +
0.3527 +
−0.1479 −
−0.2107 +
0.3502 +
−0.1254 −
0.3102i
0.2977i
0.0244i
0.3211i
0.2839i
0.0486i
0.3306i
4
0.3536
−0.0614 −
−0.3322 +
0.1768 +
0.2708 −
−0.2709 −
−0.1767 +
0.3323 +
0.3482i
0.1210i
0.3062i
0.2273i
0.2272i
0.3062i
0.1208i
5
0.3536
0.0638 −
−0.3306 −
−0.1830 +
0.2646 +
0.2784 −
−0.1642 −
−0.3376 +
0.3478i
0.1254i
0.3025i
0.2345i
0.2180i
0.3131i
0.1050i
6
0.3536
0.1881 −
−0.1534 −
−0.3513 −
−0.2204 +
0.1168 +
0.3447 +
0.2499 −
0.2994i
0.3185i
0.0395i
0.2764i
0.3337i
0.0786i
0.2501i
7
0.3536
0.2892 −
0.1196 −
−0.0936 −
−0.2727 −
−0.3525 −
−0.3040 +
−0.1449 +
0.2034i
0.3327i
0.3409i
0.2251i
0.0272i
0.1805i
0.3225i
8
0.3536
0.3461 −
0.3241 −
0.2885 −
0.2407 −
0.1828 −
0.1172 −
0.0467 −
0.0721i
0.1412i
0.2044i
0.2590i
0.3026i
0.3336i
0.3505i
9
0.3536
0.3461 +
0.3241 +
0.2885 +
0.2407 +
0.1828 +
0.1172 +
0.0467 −
0.0721i
0.1412i
0.2044i
0.2590i
0.3026i
0.3336i
0.3505i
10
0.3536
0.2892 +
0.1196 +
−0.0936 +
−0.2727 +
−0.3525 +
−0.3040 −
−0.1449 −
0.2034i
0.3327i
0.3409i
0.2251i
0.0272i
0.1805i
0.3225i
11
0.3536
0.1881 +
−0.1534 +
−0.3513 +
−0.2204 −
0.1168 −
0.3447 −
0.2499 +
0.2994i
0.3185i
0.0395i
0.2764i
0.3337i
0.0786i
0.2501i
12
0.3536
0.0638 +
−0.3306 +
−0.1830 −
0.2646 −
0.2784 +
−0.1642 +
−0.3376 −
0.3478i
0.1254i
0.3025i
0.2345i
0.2180i
0.3131i
0.1050i
13
0.3536
−0.0614 +
−0.3322 −
0.1768 −
0.2708 +
−0.2709 +
−0.1767 −
0.3323 −
0.3482i
0.1210i
0.3062i
0.2273i
0.2272i
0.3062i
0.1208i
14
0.3536
−0.1697 +
−0.1907 −
0.3527 −
−0.1479 +
−0.2107 −
0.3502 −
−0.1254 +
0.3102i
0.2977i
0.0244i
0.3211i
0.2839i
0.0486i
0.3306i
15
0.3536
−0.2514 +
0.0041 −
0.2456 +
−0.3535 −
0.2571 −
−0.0123 +
−0.2397 −
0.2486i
0.3535i
0.2543i
0.0082i
0.2427i
0.3533i
0.2599i
16
0.3536
−0.3051 +
0.1732 −
0.0062 +
−0.1839 −
0.3112 +
−0.3533 +
0.2987 −
0.1786i
0.3082i
0.3535i
0.3020i
0.1677i
0.0124i
0.1892i
where each row represents a Codebook Matrix Index (CMI) and each column (c1˜c8) represents an antenna in the multiple antenna array.
11. The method of claim 10 , wherein the values in the table are obtained based on the following equation:
V
8
(
:
,
k
,
3
)
=
1
8
[
1
ⅇ
jπ
sin
(
θ
k
)
ⅇ
j2π
sin
(
θ
k
)
ⅇ
j3π
sin
(
θ
k
)
ⅇ
j4π
sin
(
θ
k
)
ⅇ
j5π
sin
(
θ
k
)
ⅇ
j6π
sin
(
θ
k
)
ⅇ
j7π
sin
(
θ
k
)
]
,
where θ k represents an angle of a beam, k=1, 2, 3 . . . 16 and k represents the CMI.
12. The method of claim 11 , wherein θ k is given by the following equation:
θ
k
=
(
(
k
-
1
)
+
1
/
2
)
*
π
24
-
π
3
,
where k=1, 2, 3, . . . , 16, and k represents the CMI.
13. The method of claim 12 , wherein the codebook is a 4-bit codebook.
14. The method of claim 13 , wherein the table includes real and imaginary values for the second to eighth antennas (c2˜c8) of the multiple antenna array for each CMI.
15. A method for coding data in a base station including a multiple antenna array for wireless communication, comprising:
selecting a codeword from a codebook;
coding data with the selected codeword; and
transmitting the coded data,
wherein codewords in the codebook are based on the following equation:
V
8
(
:
,
k
,
3
)
=
1
8
[
1
ⅇ
jπ
sin
(
θ
k
)
ⅇ
j2π
sin
(
θ
k
)
ⅇ
j3π
sin
(
θ
k
)
ⅇ
j4π
sin
(
θ
k
)
ⅇ
j5π
sin
(
θ
k
)
ⅇ
j6π
sin
(
θ
k
)
ⅇ
j7π
sin
(
θ
k
)
]
,
where θ k resents an angle of a beam and k=1, 2, 3, . . . , 16.
16. The method of claim 15 , wherein θ k is given by the following equation:
θ
k
=
(
(
k
-
1
)
+
1
/
2
)
*
π
24
-
π
3
,
where k=1, 2, 3, . . . , 16.
17. The method of claim 15 , wherein the codebook is a 4-bit codebook.
18. The method of claim 15 , wherein the codewords in the codebook account for real and imaginary components of one or more antennas of the multiple antenna array.
19. A data structure stored on a non-transitory computer readable medium for coding data in a base station including a multiple antenna array for wireless communication, comprising:
a codebook comprising a plurality of codewords configured to be selected by a processor in the base station for coding data,
wherein the codewords in the codebook are based on values shown in the following table:
V8(:, CMI, 3) = [c1, c2, . . . c8];
CMI
c1
c2
c3
c4
c5
c6
c7
c8
1
0.3536
−0.3051 −
0.1732 +
0.0062 −
−0.1839 +
0.3112 −
−0.3533 −
0.2987 +
0.1786i
0.3082i
0.3535i
0.3020i
0.1677i
0.0124i
0.1892i
2
0.3536
−0.2514 −
0.0041 +
0.2456 −
−0.3535 +
0.2571 +
−0.0123 −
−0.2397 +
0.2486i
0.3535i
0.2543i
0.0082i
0.2427i
0.3533i
0.2599i
3
0.3536
−0.1697 −
−0.1907 +
0.3527 +
−0.1479 −
−0.2107 +
0.3502 +
−0.1254 −
0.3102i
0.2977i
0.0244i
0.3211i
0.2839i
0.0486i
0.3306i
4
0.3536
−0.0614 −
−0.3322 +
0.1768 +
0.2708 −
−0.2709 −
−0.1767 +
0.3323 +
0.3482i
0.1210i
0.3062i
0.2273i
0.2272i
0.3062i
0.1208i
5
0.3536
0.0638 −
−0.3306 −
−0.1830 +
0.2646 +
0.2784 −
−0.1642 −
−0.3376 +
0.3478i
0.1254i
0.3025i
0.2345i
0.2180i
0.3131i
0.1050i
6
0.3536
0.1881 −
−0.1534 −
−0.3513 −
−0.2204 +
0.1168 +
0.3447 +
0.2499 −
0.2994i
0.3185i
0.0395i
0.2764i
0.3337i
0.0786i
0.2501i
7
0.3536
0.2892 −
0.1196 −
−0.0936 −
−0.2727 −
−0.3525 −
−0.3040 +
−0.1449 +
0.2034i
0.3327i
0.3409i
0.2251i
0.0272i
0.1805i
0.3225i
8
0.3536
0.3461 −
0.3241 −
0.2885 −
0.2407 −
0.1828 −
0.1172 −
0.0467 −
0.0721i
0.1412i
0.2044i
0.2590i
0.3026i
0.3336i
0.3505i
9
0.3536
0.3461 +
0.3241 +
0.2885 +
0.2407 +
0.1828 +
0.1172 +
0.0467 −
0.0721i
0.1412i
0.2044i
0.2590i
0.3026i
0.3336i
0.3505i
10
0.3536
0.2892 +
0.1196 +
−0.0936 +
−0.2727 +
−0.3525 +
−0.3040 −
−0.1449 −
0.2034i
0.3327i
0.3409i
0.2251i
0.0272i
0.1805i
0.3225i
11
0.3536
0.1881 +
−0.1534 +
−0.3513 +
−0.2204 −
0.1168 −
0.3447 −
0.2499 +
0.2994i
0.3185i
0.0395i
0.2764i
0.3337i
0.0786i
0.2501i
12
0.3536
0.0638 +
−0.3306 +
−0.1830 −
0.2646 −
0.2784 +
−0.1642 +
−0.3376 −
0.3478i
0.1254i
0.3025i
0.2345i
0.2180i
0.3131i
0.1050i
13
0.3536
−0.0614 +
−0.3322 −
0.1768 −
0.2708 +
−0.2709 +
−0.1767 −
0.3323 −
0.3482i
0.1210i
0.3062i
0.2273i
0.2272i
0.3062i
0.1208i
14
0.3536
−0.1697 +
−0.1907 −
0.3527 −
−0.1479 +
−0.2107 −
0.3502 −
−0.1254 +
0.3102i
0.2977i
0.0244i
0.3211i
0.2839i
0.0486i
0.3306i
15
0.3536
−0.2514 +
0.0041 −
0.2456 +
−0.3535 −
0.2571 −
−0.0123 +
−0.2397 −
0.2486i
0.3535i
0.2543i
0.0082i
0.2427i
0.3533i
0.2599i
16
0.3536
−0.3051 +
0.1732 −
0.0062 +
−0.1839 −
0.3112 +
−0.3533 +
0.2987 −
0.1786i
0.3082i
0.3535i
0.3020i
0.1677i
0.0124i
0.1892i
where each row represents a Codebook Matrix Index (CMI) and each column (c1˜c8) represents an antenna in the multiple antenna array.
20. The data structure of claim 19 , wherein the values in the table are obtained based on the following equation:
V
8
(
:
,
k
,
3
)
=
1
8
[
1
ⅇ
jπ
sin
(
θ
k
)
ⅇ
j2π
sin
(
θ
k
)
ⅇ
j3π
sin
(
θ
k
)
ⅇ
j4π
sin
(
θ
k
)
ⅇ
j5π
sin
(
θ
k
)
ⅇ
j6π
sin
(
θ
k
)
ⅇ
j7π
sin
(
θ
k
)
]
,
where k=1, 2, 3, . . . , 16, and k represents the CMI.
21. The data structure of claim 20 , wherein θ k is given by the following equation:
θ
k
=
(
(
k
-
1
)
+
1
/
2
)
*
π
24
-
π
3
,
where k=1, 2, 3, . . . , 16, and k represents the CMI.
22. The data structure of claim 19 , wherein the codebook is a 4-bit codebook.
23. The data structure of claim 19 , wherein the table includes real and imaginary values for the second to eighth antennas (c2˜c8) of the multiple antenna array for each CMI.