US 8,543,881 B2 · Apparatus and method for high throughput unified turbo decoding

Abstract

An apparatus and method for high throughput unified turbo decoding comprising loading data from a first data window; computing a first forward state metric using the data from the first data window; storing the first forward state metric in a memory; computing a first reverse state metric using the data from the first data window; storing the first reverse state metric in the memory; and computing the log likelihood ratio (LLR) of the first forward state metric and the first reverse state metric. In one aspect, the above-mentioned steps are repeated with data from a second data window. In another aspect, extrinsic information for the first data window associated with the unified turbo decoding is computed.

Claims91

Dependent claims

A method for high throughput unified turbo decoding comprising:

loading data from a first data window;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with the unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

80 more elements

A receiver for high throughput unified turbo decoding comprising:

an antenna for receiving an electromagnetic wave comprising a received signal;
a receiver front-end for generating a digital signal from the received signal;
a demodulator coupled to the receiver front-end for demodulating the digital signal and outputting a demodulated bit stream;
and
a turbo decoder for performing the following:
loading data from a first data window of the demodulated bit stream;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window of the demodulated bit stream;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with the unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

85 more elements

A receiver for high throughput unified turbo decoding comprising:

means for receiving an electromagnetic wave comprising a received signal;
means for generating a digital signal from the received signal;
means for demodulating the digital signal and outputting a demodulated bit stream;
and
means for performing the following:
loading data from a first data window of the demodulated bit stream;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window of the demodulated bit stream;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with the unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

85 more elements

A non-transitory computer-readable medium storing a computer program, wherein execution of the computer program is for:

loading data from a first data window;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

80 more elements

A method for high throughput unified turbo decoding comprising:

loading data from a previous data window, wherein the previous data window occurs previous in time to a current data window;
loading data from the current data window;
loading data from a next data window, wherein the next data window occurs next in time to the current data window;
computing a current data window forward state metric using the data from the current data window;
storing the current data window forward state metric in a memory;
transferring the computed current data window forward state metric to the next data window to be used as a beginning forward state for computing a forward state metric in the next data window;
computing a current data window reverse state metric using the data from the current data window;
storing the current data window reverse state metric in the memory;
transferring the computed current data window reverse state metric to the previous data window to be used as a beginning reverse state for computing a reverse state metric in the previous data window;
computing a log likelihood ratio (LLR) of the current data window using the current data window forward state metric and the current data window reverse state metric;
and
computing extrinsic information for the current data window,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct,
rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

83 more elements

A receiver for high throughput unified turbo decoding comprising:

an antenna for receiving an electromagnetic wave comprising a received signal;
a receiver front-end for generating a digital signal from the received signal;
a demodulator coupled to the receiver front-end for demodulating the digital signal and outputting a demodulated bit stream;
and
a turbo decoder for performing the following:
loading data from a previous data window of the demodulated bit stream, wherein the previous data window occurs previous in time to a current data window;
loading data from the current data window of the demodulated bit stream;
loading data from a next data window of the demodulated bit stream, wherein the next data window occurs next in time to the current data window;
computing a current data window forward state metric using the data from the current data window;
transferring the computed current data window forward state metric to the next data window to be used as a beginning forward state for computing a forward state metric in the next data window;
computing a current data window reverse state metric using the data from the current data window;
transferring the computed current data window reverse state metric to the previous data window to be used as a beginning reverse state for computing a reverse state metric in the previous data window;
computing a log likelihood ratio (LLR) of the current data window using the current data window forward state metric and the current data window reverse state metric;
and
computing extrinsic information for the current data window, wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

84 more elements

A receiver for high throughput unified turbo decoding comprising:

means for loading data from a previous data window, wherein the previous data window occurs previous in time to a current data window;
means for loading data from the current data window;
means for loading data from a next data window, wherein the next data window occurs next in time to the current data window;
means for computing a current data window forward state metric using the data from the current data window;
means for transferring the computed current data window forward state metric to the next data window to be used as a beginning forward state for computing a forward state metric in the next data window;
means for computing a current data window reverse state metric using the data from the current data window;
means for transferring the computed current data window reverse state metric to the previous data window to be used as a beginning reverse state for computing a reverse state metric in the previous data window;
means for computing a log likelihood ratio (LLR) of the current data window using the current data window forward state metric and the current data window reverse state metric;
and
means for computing extrinsic information for the current data window,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

80 more elements

Dependencies are inferred from the claim text.

Facts

Application

12/558,325Filed 11 Sep 2009

Published

US 2011/0066913 A117 Mar 2011

Granted

24 Sep 2013

Term ends

Not estimatedThe source records don’t support an estimate.

Classification9 codes

H03M 13/6544
Intended application, e.g. transmission or communication standard: ieee 802.16
H03M 13/2957
Combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes: turbo…
H03M 13/2969
Particular turbo code structure: non-binary turbo codes
H03M 13/2996
Turbo codes and decoding: tail biting

Abstract

Claims91

Dependent claims

A method for high throughput unified turbo decoding comprising:

loading data from a first data window;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with the unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

80 more elements

A receiver for high throughput unified turbo decoding comprising:

an antenna for receiving an electromagnetic wave comprising a received signal;
a receiver front-end for generating a digital signal from the received signal;
a demodulator coupled to the receiver front-end for demodulating the digital signal and outputting a demodulated bit stream;
and
a turbo decoder for performing the following:
loading data from a first data window of the demodulated bit stream;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window of the demodulated bit stream;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with the unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

85 more elements

A receiver for high throughput unified turbo decoding comprising:

means for receiving an electromagnetic wave comprising a received signal;
means for generating a digital signal from the received signal;
means for demodulating the digital signal and outputting a demodulated bit stream;
and
means for performing the following:
loading data from a first data window of the demodulated bit stream;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window of the demodulated bit stream;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with the unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

85 more elements

A non-transitory computer-readable medium storing a computer program, wherein execution of the computer program is for:

loading data from a first data window;
computing a first forward state metric using the data from the first data window;
storing the first forward state metric in a memory;
computing a first reverse state metric using the data from the first data window;
storing the first reverse state metric in the memory;
computing a log likelihood ratio (LLR) of the first data window using the first forward state metric and the first reverse state metric;
loading data from a last data window;
transferring the first reverse state metric from the first data window to the last data window;
and
computing extrinsic information for the first data window associated with unified turbo decoding,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

80 more elements

A method for high throughput unified turbo decoding comprising:

loading data from a previous data window, wherein the previous data window occurs previous in time to a current data window;
loading data from the current data window;
loading data from a next data window, wherein the next data window occurs next in time to the current data window;
computing a current data window forward state metric using the data from the current data window;
storing the current data window forward state metric in a memory;
transferring the computed current data window forward state metric to the next data window to be used as a beginning forward state for computing a forward state metric in the next data window;
computing a current data window reverse state metric using the data from the current data window;
storing the current data window reverse state metric in the memory;
transferring the computed current data window reverse state metric to the previous data window to be used as a beginning reverse state for computing a reverse state metric in the previous data window;
computing a log likelihood ratio (LLR) of the current data window using the current data window forward state metric and the current data window reverse state metric;
and
computing extrinsic information for the current data window,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct,
rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

83 more elements

A receiver for high throughput unified turbo decoding comprising:

an antenna for receiving an electromagnetic wave comprising a received signal;
a receiver front-end for generating a digital signal from the received signal;
a demodulator coupled to the receiver front-end for demodulating the digital signal and outputting a demodulated bit stream;
and
a turbo decoder for performing the following:
loading data from a previous data window of the demodulated bit stream, wherein the previous data window occurs previous in time to a current data window;
loading data from the current data window of the demodulated bit stream;
loading data from a next data window of the demodulated bit stream, wherein the next data window occurs next in time to the current data window;
computing a current data window forward state metric using the data from the current data window;
transferring the computed current data window forward state metric to the next data window to be used as a beginning forward state for computing a forward state metric in the next data window;
computing a current data window reverse state metric using the data from the current data window;
transferring the computed current data window reverse state metric to the previous data window to be used as a beginning reverse state for computing a reverse state metric in the previous data window;
computing a log likelihood ratio (LLR) of the current data window using the current data window forward state metric and the current data window reverse state metric;
and
computing extrinsic information for the current data window, wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

84 more elements

A receiver for high throughput unified turbo decoding comprising:

means for loading data from a previous data window, wherein the previous data window occurs previous in time to a current data window;
means for loading data from the current data window;
means for loading data from a next data window, wherein the next data window occurs next in time to the current data window;
means for computing a current data window forward state metric using the data from the current data window;
means for transferring the computed current data window forward state metric to the next data window to be used as a beginning forward state for computing a forward state metric in the next data window;
means for computing a current data window reverse state metric using the data from the current data window;
means for transferring the computed current data window reverse state metric to the previous data window to be used as a beginning reverse state for computing a reverse state metric in the previous data window;
means for computing a log likelihood ratio (LLR) of the current data window using the current data window forward state metric and the current data window reverse state metric;
and
means for computing extrinsic information for the current data window,
wherein the extrinsic information is defined by
λ
e
i
⁡
(
t
)
=
λ
i
⁡
(
t
)
-
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
-
r
t
T
·
(
s
t
i
-
s
t
0
)
,
where λei(t) is the extrinsic information, λi(t) is a quaternary LLR,
log
⁡
(
Pr
⁡
(
c
t
=
i
)
Pr
⁡
(
c
t
=
0
)
)
is an input extrinsic LLR defined by a logarithm of a ratio of probabilities for systematic symbol ct, rtT·(sti−st0) is a systematic LLR defined by a vector dot product between systematic bit LLR vector rt and a difference between two systematic bit vectors sti and st0.

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Apparatus and method for high throughput unified turbo decoding

Life of this patent

Abstract

Claims91

Apparatus and method for high throughput unified turbo decoding

Life of this patent

Abstract

Claims91