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US 8,619,910 B1Granted
Decision feedback equalization for MIMO systems with hybrid ARQ
AssigneeMarvell International Ltd.
InventorJungwon Lee
Life of this patent
Estimating the term…
Abstract
Systems and methods are provided for decision feedback equalization (DFE) in multiple-input multiple-output (MIMO) systems with hybrid automatic repeat request (HARQ). Using a pre-equalization approach, the receiver combines received vectors by vector concatenation before equalization using DFE. Using a post-equalization approach, the receiver equalizes received vectors using DFE before combining the vectors. Cholesky factorization and QR decomposition may be used for DFE.
Claims31
A method for decoding a signal vector in a multiple-input multiple-output (MIMO) hybrid automatic repeat request (HARQ) transmission scheme, the method comprising:
- receiving multiple signal vectors corresponding to multiple asynchronous transmissions of a common transmit signal vector, the received signal vectors comprising a first signal vector corresponding to a transmission of the common transmit signal vector and a second signal vector corresponding to a retransmission of the common transmit signal vector, wherein each of the received signal vectors is associated with a channel state matrix;
- concatenating the received signal vectors into a combined received signal vector;
- concatenating each channel state matrix associated with the received signal vectors into a combined channel state matrix;
- after the concatenations, matched filtering the combined received signal vector using the combined channel state matrix;
- decision feedback equalizing the matched filtered combined received signal vector, wherein the decision feedback equalizing comprises incrementally computing a projected received signal, {tilde over (w)}n, and a triangular matrix {tilde over (R)}n for an n-th transmission of the common transmit signal vector where
- w
- ~
- n
- =
- Q
- n
-
- *
- ~
-
- [
- w
- ~
- n
- -
- 1
- y
- n
- ]
- ,
- H
- ~
- n
- =
- [
- R
- ~
- n
- -
- 1
- H
- n
- ]
- ,
- and where a QR decomposition of the channel state matrix for the n-th transmission of the common transmit signal vector {tilde over (H)}n is given by
- {tilde over (H)}n={tilde over (Q)}n{tilde over (R)}n.
- and where H1=Q1R1, {tilde over (w)}1=Q1*y1, and yn is the n-th received signal vector corresponding to the common transmit signal vector;
- and
- decoding an estimated transmit signal vector from the equalized combined received signal vector.
41 more elements
A method for decoding a signal vector in a multiple-input multiple-output (MIMO) hybrid automatic repeat request (HARQ) transmission scheme, comprising:
- receiving multiple signal vectors corresponding to a common transmit signal vector, wherein each of the received signal vectors is associated with a channel state matrix;
- decision feedback equalizing each of the received signal vectors using an associated channel state matrix, wherein the decision feedback equalizing comprises incrementally computing a projected received signal, {tilde over (w)}n, and a triangular matrix {tilde over (R)}n for an n-th transmission of the common transmit signal vector where
- w
- ~
- n
- =
- Q
- n
-
- *
- ~
-
- [
- w
- ~
- n
- -
- 1
- y
- n
- ]
- ,
- H
- ~
- n
- =
- [
- R
- ~
- n
- -
- 1
- H
- n
- ]
- ,
- and where a QR decomposition of the channel state matrix for the n-th transmission of the common transmit signal vector {tilde over (H)}n is given by
- {tilde over (H)}n={tilde over (Q)}n{tilde over (R)}n.
- and where H1=Q1R1, {tilde over (w)}1=Q1*y1, and yn is the n-th received signal vector corresponding to the common transmit signal vector;
- maximal ratio combining the equalized received signal vectors;
- and
- decoding an estimated transmit signal vector from the combined equalized received signal vectors.
39 more elements
A system for decoding a signal vector in a multiple-input multiple-output (MIMO) hybrid automatic repeat request (HARQ) transmission scheme, the system comprising:
- a receiver that:
- receives multiple signal vectors corresponding to multiple asynchronous transmissions of a common transmit signal vector, the received signal vectors comprising a first signal vector corresponding to a transmission of the common transmit signal vector and a second signal vector corresponding to a retransmission of the common transmit signal vector, wherein each of the received signal vectors is associated with a channel state matrix, and
- concatenates the received signal vectors into a combined received signal vector and concatenates each channel state matrix associated with the received signal vectors into a combined channel state matrix;
- a matched filter that, after the concatenations, filters the combined received signal vector using the combined channel state matrix;
- a decision feedback equalizer that equalizes the matched filtered combined received signal vector, wherein the decision feedback equalizer incrementally computes a projected received signal, {tilde over (w)}n, and a triangular matrix {tilde over (R)}n for an n-th transmission of the common transmit signal vector where
- w
- ~
- n
- =
- Q
- n
-
- *
- ~
-
- [
- w
- ~
- n
- -
- 1
- y
- n
- ]
- ,
- H
- ~
- n
- =
- [
- R
- ~
- n
- -
- 1
- H
- n
- ]
- ,
- and where a QR decomposition of the channel state matrix for the n-th transmission of the common transmit signal vector {tilde over (H)}n is given by
- {tilde over (H)}n={tilde over (Q)}n{tilde over (R)}n.
- and where H1=Q1R1, and yn is the n-th received signal vector corresponding to the common transmit signal vector;
- and
- a decoder that decodes an estimated transmit signal vector from the equalized combined received signal vector.
41 more elements
A system for decoding a signal vector in a multiple-input multiple-output (MIMO) hybrid automatic repeat request (HARQ) transmission scheme, the system comprising:
- a receiver that receives multiple signal vectors corresponding to a common transmit signal vector, wherein each of the received signal vectors is associated with a channel state matrix;
- decision feedback equalizer that equalizes each of the received signal vectors using an associated channel state matrix, wherein the decision feedback equalizer incrementally computes a projected received signal, {tilde over (w)}n, and a triangular matrix {tilde over (R)}n for an n-th transmission of the common transmit signal vector where
- w
- ~
- n
- =
- Q
- n
-
- *
- ~
-
- [
- w
- ~
- n
- -
- 1
- y
- n
- ]
- ,
- H
- ~
- n
- =
- [
- R
- ~
- n
- -
- 1
- H
- n
- ]
- ,
- and where a QR decomposition of the channel state matrix for the n-th transmission of the common transmit signal vector {tilde over (H)}n is given by
- {tilde over (H)}n={tilde over (Q)}n{tilde over (R)}n.
- and where H1=Q1=R1, {tilde over (w)}1=Q1*y1, and yn is the n-th received signal vector corresponding to the common transmit signal vector;
- a maximal ratio combiner that combines the equalized received signal vectors;
- and
- a decoder that determines an estimated transmit signal vector from the combined equalized received signal vectors.
39 more elements
Dependencies are inferred from the claim text.