Space-time block-coding (STBC) with multiple streams in orhogonal frequency division mulitplexing (OFDM) for wireless local area networks (WLAN) and error metrics for soft decision with channel information
View Patent ↗A method of receiving data over N receiving antennas from M transmitting antennas, where M and N are integers, includes the steps of receiving N signals over the N receiving antennas, applying the N signals to a space/time decoder, determining noise powers for N channels, with the N channels being based on the N signals, applying Viterbi filtering to the N channels utilizing the noise powers and deriving received data from the filtered N channels.
1. A method of receiving data over N receiving antennas from M transmitting antennas, where M and N are integers, the method comprising the steps of:
receiving N signals over the N receiving antennas;
applying the N signals to a space/time decoder;
determining noise powers for N channels, with the N channels being based on the N signals, said noise power determination being based on N combinations of noise power scaling;
applying Viterbi filtering to the N channels utilizing the noise powers; and
deriving received data from the filtered N channels.
2. A method according to claim 1 , wherein the step of determining noise powers further comprises removing interference terms between the N channels.
3. A method according to claim 1 , wherein the step of determining noise powers comprises zero-forcing terms equivalent to relationships between signals sent from the M transmitting antennas to the N receiving antennas to determine channel information.
4. A method according to claim 3 , wherein when N=2, the relationships comprise:
[
r
1
r
2
]
=
[
H
1
G
1
H
2
G
2
]
[
c
1
c
2
]
+
[
n
1
n
2
]
where
,
c
1
=
[
c
11
c
12
]
,
c
2
=
[
c
21
c
22
]
,
r
1
=
[
r
1
(
t
1
)
r
1
*
(
t
2
)
]
,
r
2
=
[
r
2
(
t
1
)
r
2
*
(
t
2
)
]
,
H
i
=
[
h
1
i
h
2
i
h
2
i
*
-
h
1
i
*
]
,
G
i
=
[
h
3
i
h
4
i
h
4
i
*
-
h
3
i
*
]
and the channel information of each space-time block-coding (STBC) symbol after crosstalk cancellation, Ni, comprises:
E
(
[
N
1
N
2
]
[
N
1
*
N
2
*
]
)
=
[
H
~
*
(
I
+
G
^
)
H
~
-
H
~
*
(
(
H
2
H
1
-
1
)
*
+
G
1
G
2
-
1
)
H
~
G
~
*
(
H
1
H
1
-
1
+
(
G
1
G
2
-
1
)
*
)
H
~
G
~
*
(
I
+
H
^
)
G
~
]
where
,
G
^
=
G
1
(
G
2
*
G
2
)
-
1
G
1
*
,
H
^
=
H
2
(
H
1
*
H
1
)
-
1
H
2
*
,
and
where
,
H
~
=
H
1
-
G
1
G
2
-
1
H
2
,
G
~
=
G
2
-
H
2
H
1
-
1
G
1
.
5. A method according to claim 4 , wherein when N is greater than M, the channel information can be written as sums of weighted scalar values.
6. A method according to claim 1 , wherein the step of receiving N signals comprises receiving the N signals that have been coded through space-time block-coding.
7. A method according to claim 1 , wherein the step of applying Viterbi filtering to the N channels comprises applying soft decision Viterbi filtering to the N channels.
8. A method according to claim 1 , further comprising utilizing the noise powers in decoding of the N channels, wherein the decoding is performed according to one of turbo decoding and low density parity check block decoding.
9. A method according to claim 1 , further comprising at least one of band pass filtering of the N received signals, analog-to-digital converting of the N received signals, fast Fourier transforming the N Viterbi filtered channels and multiplexing the N Viterbi filtered channels.
10. A receiver for receiving data over N receiving antennas transmitted from M transmitting antennas, where N and M are integers, the receiver comprising:
receiving means for receiving N signals over the N receiving antennas;
applying means for applying the N signals to a space/time decoder;
determining means for determining noise powers for N channels, with the N channels being based on the N signals, said noise power determining means being based on N combinations of noise power scaling;
filtering means for applying Viterbi filtering to the N channels utilizing the noise powers; and
deriving means for deriving received data from the filtered N channels.
11. A receiver according to claim 10 , wherein the determining means further comprises interference removing means for removing interference terms between the N channels.
12. A receiver according to claim 10 , wherein the determining means comprises zero-forcing means for zero-forcing terms equivalent to relationships between signals sent from the M transmitting antennas to the N receiving antennas to determine channel information.
13. A receiver according to claim 12 , wherein the relationships comprise:
[
r
1
r
2
]
=
[
H
1
G
1
H
2
G
2
]
[
c
1
c
2
]
+
[
n
1
n
2
]
where
,
c
1
=
[
c
11
c
12
]
,
c
2
=
[
c
21
c
22
]
,
r
1
=
[
r
1
(
t
1
)
r
1
*
(
t
2
)
]
,
r
2
=
[
r
2
(
t
1
)
r
2
*
(
t
2
)
]
,
H
i
=
[
h
1
i
h
2
i
h
2
i
*
-
h
1
i
*
]
,
G
i
=
[
h
3
i
h
4
i
h
4
i
*
-
h
3
i
*
]
and the channel information of each STBC symbol after crosstalk cancellation, Ni, comprises:
E
(
[
N
1
N
2
]
[
N
1
*
N
2
*
]
)
=
[
H
~
*
(
I
+
G
^
)
H
~
-
H
*
~
(
(
H
2
H
1
-
1
)
*
+
G
1
G
2
-
1
)
H
~
G
*
~
(
H
1
H
1
-
1
+
(
G
1
G
2
-
1
)
*
)
H
~
G
*
~
(
I
+
H
^
)
G
~
]
where
,
G
^
=
G
1
(
G
2
*
G
2
)
-
1
G
1
*
,
H
^
=
H
2
(
H
1
*
H
1
)
-
1
H
2
*
,
and
where
H
~
=
H
1
-
G
1
G
2
-
1
H
2
,
G
~
=
G
2
-
H
2
H
1
-
1
G
1
.
14. A receiver according to claim 13 , wherein when N is greater than M, the channel information can be written as sums of weighted scalar values.
15. A receiver according to claim 10 , wherein the receiving means comprises receiving means for receiving the N signals that have been coded through space-time block-coding.
16. A receiver according to claim 10 , wherein the applying means comprises applying means for applying soft decision Viterbi filtering to the N channels.
17. A receiver according to claim 10 , further comprising utilizing means for utilizing the noise powers in decoding of the N channels, wherein the decoding is performed according to one of turbo decoding and low density parity check block decoding.
18. A receiver according to claim 10 , further comprising at least one of band pass filtering means for filtering of the N received signals, analog-to-digital converting means for analog-to-digital converting of the N received signals, fast Fourier transforming means for fast Fourier transforming the N Viterbi filtered channels and multiplexing means for multiplexing the N Viterbi filtered channels.
19. A receiver for receiving data over N receiving antennas transmitted from M transmitting antennas, where N and M are integers, the receiver comprising:
N receiving antennas, configured to receive N signals;
a space/time decoder, configured to receive the N signals and supply N channels being based on the N signals; and
a multiplexer, configured to provide received data from the N channels;
wherein the space/time decoder is configured to determine noise powers for N channels and to apply Viterbi filtering to the N channels utilizing the noise powers, said noise power determination being based on N combinations of noise power scaling.
20. A receiver according to claim 19 , wherein the space/time decoder is configured to remove interference terms between the N channels.
21. A receiver according to claim 19 , wherein the space/time decoder is configured to zero-force terms equivalent to relationships between signals sent from the M transmitting antennas to the N receiving antennas to determine channel information.
22. A receiver according to claim 21 , wherein the relationships comprise:
[
r
1
r
2
]
=
[
H
1
G
1
H
2
G
2
]
[
c
1
c
2
]
+
[
n
1
n
2
]
where
,
c
1
=
[
c
11
c
12
]
,
c
2
=
[
c
21
c
22
]
,
r
1
=
[
r
1
(
t
1
)
r
1
*
(
t
2
)
]
,
r
2
=
[
r
2
(
t
1
)
r
2
*
(
t
2
)
]
,
H
i
=
[
h
1
i
h
2
i
h
2
i
*
-
h
1
i
*
]
,
G
i
=
[
h
3
i
h
4
i
h
4
i
*
-
h
3
i
*
]
and the channel information of each STBC symbol after crosstalk cancellation, Ni, comprises:
E
(
[
N
1
N
2
]
[
N
1
*
N
2
*
]
)
=
[
H
~
*
(
I
+
G
^
)
H
~
-
H
*
~
(
(
H
2
H
1
-
1
)
*
+
G
1
G
2
-
1
)
H
~
G
*
~
(
H
1
H
1
-
1
+
(
G
1
G
2
-
1
)
*
)
H
~
G
*
~
(
I
+
H
^
)
G
~
]
where
,
G
^
=
G
1
(
G
2
*
G
2
)
-
1
G
1
*
,
H
^
=
H
2
(
H
1
*
H
1
)
-
1
H
2
*
,
and
where
H
~
=
H
1
-
G
1
G
2
-
1
H
2
,
G
~
=
G
2
-
H
2
H
1
-
1
G
1
.
23. A receiver according to claim 22 , wherein when N is greater than M, the channel information can be written as sums of weighted scalar values.
24. A receiver according to claim 19 , wherein the space/time decoder is configured to apply soft decision Viterbi filtering to the N channels.
25. A receiver according to claim 19 , wherein the space/time decoder is configured to utilize the noise powers in decoding of the N channels, wherein the decoding is configured to perform according to one of turbo decoding and low density parity check block decoding.
26. A receiver method according to claim 19 , further comprising at least one of a band pass filter, an analog-to-digital converter, a fast Fourier transformer and a multiplexer.