US 9,425,871 B2 · 4TX codebook enhancement in LTE

Abstract

Channel state information (CSI) feedback in a wireless communication system is disclosed. A precoding matrix is generated for multi-antenna transmission based on precoding matrix indicator (PMI) feedback, wherein the PMI indicates a choice of precoding matrix derived from a matrix multiplication of two matrices from a first codebook and a second codebook. In one embodiment, the first codebook comprises at least a first precoding matrix constructed with a first group of adjacent Discrete-Fourier-Transform (DFT) vectors. In another embodiment, the first codebook comprises at least a second precoding matrix constructed with a second group of uniformly distributed non-adjacent DFT vectors. In yet another embodiment, the first codebook comprises at least a first precoding matrix and a second precoding matrix, where said first precoding matrix is constructed with a first group of adjacent DFT vectors, and said second precoding matrix is constructed with a second group of uniformly distributed non-adjacent DFT vectors.

Claims29

Dependent claims

A method of channel state information (CSI) feedback in a wireless communication system, comprising:

receiving one or more precoding matrix indicator (PMI) signals from a remote transceiver;
and
generating a precoding matrix W derived from a matrix multiplication of two matrices W1 and W2, where said precoding matrix W is applicable to precoding one or more layers of data streams, matrix W1 selected from a first codebook C1 based on a first group of bits in the PMI signals, and matrix W2 selected from a second codebook C2 based on a second group of bits in the PMI signals, wherein the first codebook C1 comprises the following W1 matrices:
C1={W1(0),W1(1),W1(2), . . . ,W1(15)}
and matrix W1(k), for k=0, 1, . . . , 15, can be written in the form
W
1
(
k
)
=
[
X
(
k
)
0
0
X
(
k
)
]
,
where 0 is a matrix with all entries equal to zero and X(k) is a matrix having two or more columns where at least one column is equal to bk mod N and at least one column is equal to b(k+N/2)mod N where
b
k
=
[
1
ⅇ
j2π
⁢
⁢
k
/
N
]
and N=32.

36 more elements

A method of channel state information (CSI) feedback in a wireless communication system, comprising:

receiving one or more precoding matrix indicator (PMI) signals from a remote transceiver, and
generating a precoding matrix W derived from a matrix multiplication of two matrices W1 and W2, where said precoding matrix W is applicable to precoding one or more layers of data streams, matrix W1 selected from a first codebook C1 based on a first group of bits in the PMI signals, and matrix W2 selected from a second codebook C2 based on a second group of bits in the PMI signals, wherein the first codebook C1 comprises the following W1 matrices:
C1={W1(0),W1(1),W1(2), . . . ,W1(15)}
and matrix W1(k), for k=0, 1, . . . , 15, can be written in the form
W
1
(
k
)
=
[
X
(
k
)
0
0
X
(
k
)
]
,
where 0 is a matrix with all entries equal to zero,
wherein the set of matrices
{
[
X
(
[
i
1
]
)
0
0
X
(
[
i
1
]
)
]
:
i
1
=
8
,
9
,
…
⁢
,
15
}
are in C1 where
X([i1])ε{[b(i1−8)mod Nb((i1−8)+8)mod Nb((i1−8)+16)mod Nb((i1−8)+24)mod N]},
b
k
=
[
1
ⅇ
j2π
⁢
⁢
k
/
N
]
,
and N=32.

71 more elements

A method of channel state information (CSI) feedback in a wireless communication system, node comprising:

receiving one or more precoding matrix indicator (PMI) signals from a remote transceiver, and
generating a precoding matrix W derived from a matrix multiplication of two matrices W1 and W2, where said precoding matrix W is applicable to precoding one or more layers of data streams, matrix W1 is selected from a first codebook C1 based on a first group of bits in the PMI signals, and matrix W2 is selected from a second codebook C2 based on a second group of bits in the PMI signals, wherein the first codebook C1 comprises the following W1 matrices constructed by non-adjacent Discrete Fourier Transform (DFT) vectors:
B=[b0b1 . . . b31]
bk=[1ej2πk/32]T, for k=0,1, . . . ,31
X(k)=[bkb(k+8)mod 32b(k+16)mod 32b(k+24)mod 32], for k=0,1, . . . ,15
W
1
(
k
)
=
[
X
(
k
)
0
0
X
(
k
)
]
⁢
⁢
for
⁢
⁢
k
=
0
,
1
,
…
⁢
,
15
C1={W1(0),W1(1), . . . ,W1(15),} for k=0,1, . . . ,15.

36 more elements

A method of channel state information (CSI) feedback in a wireless communication system, node comprising:

receiving one or more precoding matrix indicator (PMI) signals from a remote transceiver, and
generating a precoding matrix W derived from a matrix multiplication of two matrices W1 and W2, where said precoding matrix W is applicable to precoding one or more layers of data streams, matrix W1 is selected from a first codebook C1 based on a first group of bits in the PMI signals, and matrix W2 is selected from a second codebook C2 based on a second group of bits in the PMI signals, wherein the first codebook C1 is constructed as
C1={W1(0),W1(1), . . . ,W1(15))} for k=0,1, . . . ,15.
where
W
1
(
k
)
=
[
X
(
k
)
0
0
X
(
k
)
]
⁢
⁢
for
⁢
⁢
k
=
0
,
1
,
…
⁢
,
15
using
X(k)=[bkb(k+)mod 32b(k+16)mod 32b(k+24)mod 32],
bk=[1ej2πk/32]T, for k=0,1, . . . ,31.

37 more elements

A method of channel state information (CSI) feedback in a wireless communication system, node comprising:

receiving one or more precoding matrix Indicator (PMI) signals from a remote transceiver;
and
generating a precoding matrix W derived from a matrix multiplication of two matrices W1 and W2, where said precoding matrix W is applicable to precoding one or more layers of data streams, matrix W1 is selected from a first codebook using a PMI value i1, and matrix W2 is selected from a second codebook using a PMI value i2 where the first matrix is selected according to
W
i
(
ⅈ
1
)
=
[
X
(
ⅈ
1
)
0
0
X
(
ⅈ
1
)
]
⁢
⁢
for
⁢
⁢
ⅈ
i
=
0
,
1
,
…
⁢
,
15
with
X(k)=[bk mod 32b(k+8)mod 32b(k+16)mod 32b(k+24)mod 32]
bk=vk′
vk′=[1ej2πk/32]T.

41 more elements

Dependencies are inferred from the claim text.

4TX codebook enhancement in LTE

Life of this patent

4TX codebook enhancement in LTE

Life of this patent

Abstract

Claims29