US2013215948A1PendingUtilityA1
Adaptive transmission and receiving method and device in wireless communication system with multiple antennas
Assignee: RES INST ELECTRONICS & TELECOMMPriority: Apr 1, 2003Filed: Mar 18, 2013Published: Aug 22, 2013
Est. expiryApr 1, 2023(expired)· nominal 20-yr term from priority
H04L 1/0003H04L 1/0015H04B 7/0854H04B 17/336H04L 25/0202H04B 7/0626H04B 7/0413H04B 7/0697H04L 1/0026H04L 1/0618H04B 7/0417H04B 7/0689H04L 1/0009H04B 7/0669Y02D30/70
54
PatentIndex Score
0
Cited by
0
References
0
Claims
Abstract
Disclosed is an adaptive transmit and receive method and device in a multiple-antenna wireless communication system. A transmit mode comprises different main transmit modes each of which includes one or both of a sub-transmit mode based on STBC and a sub-transmit mode based on SM. A receiver calculates an STBC performance parameter and a SM performance parameter, and a transmitter uses the parameters to determine a main transmit mode with maximum data rates and select a sub-transmit mode for minimizing power consumption. The transmitter channel-encodes, modulates and antenna-maps input data according to the selected transmit mode, and outputs results to the receiver. The receiver antenna/symbol-demodulates and channel-decodes the received data.
Claims
exact text as granted — not AI-modifiedWhat is claimed is:
1 . An adaptive transmit method of a transmitter in a wireless communication system with multiple antennas for transmitting data to a receiver with a plurality of receive antennas from the transmitter with a plurality of transmit antennas through an MIMO (multiple input multiple output) channel, comprising:
(a) determining a channel coding method, a modulation method, and an antenna transmit method so as to support different data rates according to a characteristic of the MIMO channel, wherein the channel coding method, the modulation method, and the antenna transmit method are classified according to a main transmit mode for supporting different data rates, and the main transmit mode includes either or both of a sub-transmit mode based on the STBC (space time block code) and a sub-transmit mode based on the SM (spatial multiplexing); (b) encoding input data according to the determined main transmit mode; (c) modulating the data encoded in (b) according to the determined sub-transmit mode, mapping them to modulation symbols, and outputting results; and (d) mapping the data modulated in (c) to symbol vectors to be transmitted through each transmit antenna according to the determined sub-transmit mode, and outputting results.
2 . The adaptive transmit method of claim 1 , wherein the characteristic of the MIMO channel is indicated by an antenna transmit performance parameter produced and fed back by the receiver.
3 . The adaptive transmit method of claim 1 , wherein (a) comprises:
determining a main transmit mode that provides the highest data rates from among the transmit modes (which include the main transmit mode and the sub-transmit mode) that satisfy the performance required according to the characteristic of the MIMO channel, and determining a sub-transmit mode for reducing a transmit power from the determined main transmit mode.
4 . The adaptive transmit method of claim 1 , wherein (d) comprises:
performing antenna mapping based on STBC when performing symbol mapping having a first symbol constellation on the same main transmit mode in (c), and (d) comprises: performing antenna mapping based on SM when performing symbol mapping having a second symbol constellation on the same main transmit mode in (c).
5 . The adaptive transmit method of claim 1 , wherein (a) comprises:
(i) comparing an STBC performance parameter which is one of parameters for showing the characteristic of the MIMO channel with a previously stored STBC threshold value to select one of the main transmit modes having a sub-transmit mode based on the STBC; (ii) comparing an SM performance parameter, which is one of parameters for showing the characteristic of the MIMO channel, with a previously stored SM threshold value to select one of the main transmit modes having a sub-transmit mode based on the SM; and (iii) comparing the main transmit mode selected in (i) with the main transmit mode selected in (ii) to determine a final transmit mode (which includes a main transmit mode and a sub-transmit.
6 . The adaptive transmit method of claim 5 , wherein (i) comprises: selecting a main transmit mode which has a minimum positive number obtained by subtracting the STBC threshold value from the STBC performance parameter, and
(ii) comprises: selecting a main transmit mode which has a minimum positive number obtained by subtracting the SM threshold value from the SM performance parameter.
7 . The adaptive transmit method of claim 5 , wherein the main transmit mode has indexes in the ascending order of data rates, and
(iii) comprises: determining whether the main transmit mode selected in (i) is greater than the main transmit mode selected in (ii); determining the main transmit mode selected in (i) and a sub-transmit mode based on STBC of the selected main transmit mode as final transmit modes (which include a main transmit mode and a sub-transmit mode), when the main transmit mode selected in (i) is greater than the main transmit mode selected in (ii); and determining the main transmit mode selected in (i) and a sub-transmit mode based on STBC of the selected main transmit mode as final transmit modes (which include a main transmit mode and a sub-transmit mode), when the main transmit mode selected in (i) is matched with the main transmit mode selected in (ii), and the value obtained by subtracting the STBC threshold value from the STBC performance parameter is greater than the value obtained by subtracting the SM threshold value from the SM performance parameter.
8 . The adaptive transmit method of claim 7 , comprising:
determining the main transmit mode selected in (ii) and a sub-transmit mode based on SM of the selected main transmit mode as final transmit modes (which include a main transmit mode and a sub-transmit mode), when the main transmit mode selected in (ii) is greater than the main transmit mode selected in (i); and determining the main transmit mode selected in (ii) and a sub-transmit mode based on SM of the selected main transmit mode as final transmit modes (which include a main transmit mode and a sub-transmit mode), when the main transmit mode selected in (i) is matched with the main transmit mode selected in (ii), and the value obtained by subtracting the SM threshold value from the SM performance parameter is greater than the value obtained by subtracting the STBC threshold value from the STBC performance parameter.
9 . An adaptive receiving method of a receiver in a wireless communication system with multiple antennas for transmitting data to the receiver with a plurality of receive antennas from a transmitter with a plurality of transmit antennas through an MIMO (multiple input multiple output) channel, comprising:
(a) extracting symbol information for each antenna from a signal received through the MIMO channel according to a channel coding method, a modulation method, and an antenna transmit method determined by the transmitter so as to support different data rates according to a characteristic of the MIMO channel, wherein the channel coding method, the modulation method, and the antenna transmit method are classified according to a main transmit mode for supporting different data rates, and the main transmit mode includes either or both of a sub-transmit mode based on the STBC (space time block code) and a sub-transmit mode based on the SM (spatial multiplexing); (b) performing channel decoding according to the extracted symbol information for each transmit antenna, and estimating transmitted data information; and (c) extracting a parameter used by the transmitter for determining the channel coding method, the modulation method, and the antenna transmit method by using an MIMO channel response estimated from the signal received through the MIMO channel.
10 . The adaptive receive method of claim 9 , wherein (c) comprises:
(i) calculating an STBC performance parameter which is one of parameters for showing characteristics of the MIMO channel by using the estimated MIMO channel response; and (ii) calculating an SM performance parameter which is one of parameters for showing the characteristics of the MIMO channel by using the estimated MIMO channel response.
11 . The adaptive receive method of claim 10 , wherein (i) comprises:
calculating a channel power sum by using the estimated MIMO channel response; and calculating the STBC performance parameter by combining the calculated channel power sum with the estimated MIMO channel response.
12 . The adaptive receive method of claim 11 , wherein the STBC performance parameter SB satisfies the subsequent equation:
S
B
=
10
log
10
(
SNR
SBC
)
=
10
log
10
(
H
2
M
E
S
N
0
)
where
H
2
=
∑
p
=
1
N
∑
q
=
1
M
h
p
,
q
2
,
H
=
[
h
1
,
1
h
1
,
2
…
h
1
,
M
h
2
,
1
h
2
,
2
…
h
2
,
M
⋮
⋮
⋱
⋮
h
N
,
1
h
N
,
2
…
h
N
,
M
]
is an MIMO channel response, E s is a transmit symbol energy, and N 0 is distribution of complex additive white noise.
13 . The adaptive receive method of claim 10 , wherein (i) comprises:
calculating a linear equalization matrix by using the estimated MIMO channel response; calculating a transmit antenna post-processing SNR by using the calculated linear equalization matrix; and calculating the SM performance parameter by using the calculated transmit antenna post-processing SNR.
14 . The adaptive receive method of claim 13 , wherein the linear equalization matrix G follows the equation G=(H H H) −1 H H in the case of a ZF (zero forcing) linear equalization criterion.
15 . The adaptive receive method of claim 13 , wherein the linear equalization matrix G follows the equation
G
=
(
H
H
H
+
N
0
ME
S
I
M
)
-
1
H
H
in the case of a MMSE (minimum mean square error) linear equalization criterion.
16 . The adaptive receive method of claim 14 , wherein the transmit antenna post-processing SNR follows the equation
SNR
SM
,
q
=
E
S
g
q
H
h
q
MN
0
+
E
S
∑
j
≠
q
g
q
H
h
j
where SNR SM,q is a post-processing SNR of the symbol transmitted to the q-th transmit antenna, h q is the q-th column vector of H, and g q is the q-th column vector of the linear equalization matrix G .
17 . The adaptive receive method of claim 16 , wherein the SM performance parameter S M follows the equation S M min q 10log 10 (SNR SM,q ) in the case of setting the minimum value of the antenna post-processing SNR as a reference.
18 . The adaptive receive method of claim 16 , wherein the SM performance parameter S M follows the equation
S
M
=
1
M
∑
q
=
1
M
10
log
10
(
SNR
SM
,
q
)
in the case of setting the geometric mean of the antenna post-processing SNR as a reference.
19 . The adaptive receive method of claim 17 , wherein in the case that a number of the transmit antennas is 2, and a number of the receive antennas is greater than 3, when the transmit antenna post-processing SNR calculated based on the ZF linear equalization criterion is given as the equation
SNR
SM
,
q
=
1
2
(
H
H
H
)
qq
-
1
E
S
N
0
=
α
q
(
1
-
ρ
2
)
SNR
SBC
where A qq −1 is the (q,q)-th element of A −1 ,
α
q
=
h
q
2
H
2
is a channel power ratio of the q-th transmit antenna,
ρ
=
h
1
H
h
2
h
1
h
2
is a channel correlation between two transmit antennas, and ||v|| is a norm of v, the SM performance parameter S M in the case of setting the minimum value of the antenna post-processing SNR as a reference follows the equation S M =10log 10 (α min (1−ρ 2 ))+S B where α min =min q α q .
20 . The adaptive receive method of claim 18 , wherein in the case that a number of the transmit antennas is 2, and a number of the receive antennas is greater than 3, when the transmit antenna post-processing SNR calculated based on the ZF linear equalization criterion is given as the equation
SNR
SM
,
q
=
1
2
(
H
H
H
)
qq
-
1
E
S
N
0
=
α
q
(
1
-
ρ
2
)
SNR
SBC
where A qq −1 is the (q,q)-th element of A −1 ,
α
q
=
h
q
2
H
2
is a channel power ratio of the q-th transmit antenna,
ρ
=
h
1
H
h
2
h
1
h
2
is a channel correlation between two transmit antennas, and ||v|| is a norm of v, the SM performance parameter S M in the case of setting the geometric mean of the antenna post-processing SNR as a reference follows the equation S M =10log 10 (√{square root over (α 1 α 2 )}(1−ρ 2 ))+S B where α 1 and α 2 are channel power ratio for each transmit antenna, and ρ is a channel correlation of the transmit antenna.Cited by (0)
No later patents cite this yet.
References (0)
No backward citations on record.