Data transmitting and receiving method using phase shift based precoding and transceiver supporting the same
View Patent ↗A method for performing a precoding based on a generalized phase shift or a precoding based on an extended phase shift in a Multi-Input Multi-Output (MIMO) system employing several sub-carriers, and a transceiver for supporting the same are disclosed. A phase-shift-based precoding matrix is generalized by multiplying a diagonal matrix for a phase shift by a unitary matrix for maintaining orthogonality between sub-carriers. In this case, a diagonal matrix part may be extended by multiplying a precoding matrix for removing an interference between sub-carriers by a diagonal matrix for a phase shift. By generalization and extension of the phase-shift-based precoding, a transceiver is more simplified, and a communication efficiency increases.
1. A method for transmitting signals at a transmitter of a Multi-Input Multi-Output (MIMO) system using a plurality of antennas, the method comprising:
performing a precoding on one or more streams of signals at a precoder to map the one or more streams to the plurality of antennas using a precoding matrix with a subset index (i) selected from a subset of a codebook, wherein the subset index (i) cyclically increases every (v) contiguous resource indices within a range from 0 to (N restrict )−1, wherein (v) is a predetermined integer value,
wherein the codebook includes (N) precoding matrices of {P 0 , P 1 , P 2 , . . . P (N)-1 }, each matrix having a codebook index (j), (j)=0, 1, . . . , (N)−1,
wherein the subset of the codebook includes (N restrict ) precoding matrices having matrix elements corresponding to one of ‘1’, ‘−1’, ‘j’ and ‘−j’ and represented as:
{P a , P b , P c , . . . P d }, wherein a, b, c, . . . , dε{0, 1, 2, . . . , (N)−1}, the number of a, b, c, . . . , d equals to the (N restrict ), and a<b<c< . . . <d,
wherein the subset index (i) of each (N restrict ) precoding matrix, selected from the (N) precoding matrices, is defined as 0, 1, . . . , (N restrict )−1 to correspond to each codebook index of the selected precoding matrices, and
wherein each of the subset indices of 0, 1, . . . , (N restrict )−1 corresponds in the order of a, b, c, . . . , d; and
transmitting the precoded signals to a receiver.
2. The method of claim 1 , wherein the subset includes (N restrict ) precoding matrices of:
{W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 },
wherein each of precoding matrices of {W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 } corresponds to each of {P a , P b , P c , . . . P d }.
3. The method of claim 1 , wherein (i)=(s) mod (N restrict ), wherein ‘mod’ indicates a modulo operation, wherein (s) is a variable which increases per every (v) contiguous subcarriers.
4. The method of claim 1 , wherein (v) corresponds to a spatial multiplexing rate.
5. A transceiver for transmitting signals in a Multi-Input Multi-Output (MIMO) system, the transceiver comprising:
a precoder for performing a precoding on one or more streams of signals using a precoding matrix with a subset index (i) selected from a subset of a codebook, wherein the subset index (i) cyclically increases every (v) contiguous resource indices within a range from 0 to (N restrict )−1 wherein (v) is a predetermined integer value,
wherein the codebook includes (N) precoding matrices of {P 0 , P 1 , P 2 , P (N)-1 }, each matrix having a codebook index (j), (j)=0, 1, . . . , (N)−1,
wherein the subset of the codebook includes (N restrict ) precoding matrices having matrix elements corresponding to one of ‘1’, ‘−1’, ‘j’ and ‘−j’ and represented as:
{P a , P b , P c , . . . P d }, wherein a, b, c, . . . , dε{0, 1, 2, . . . , (N)−1}, the number of a, b, c, . . . , d equals to the (N restrict ), and a<b<c< . . . <d,
wherein the subset index (i) of each (N restrict ) precoding matrix, selected from the (N) precoding matrices, is defined as 0, 1, . . . , (N restrict )−1 to correspond to each codebook index of the selected precoding matrices, and
wherein each of the subset indices of 0, 1, . . . , (N restrict )−1 corresponds in the order of a, b, c, . . . , d; and
a plurality of antennas for transmitting the precoded signals to a receiver.
6. The transceiver of claim 5 , further comprising:
an encoder for encoding input signals to output the one or more streams of signals.
7. The transceiver of claim 5 , wherein the subset includes (N restrict ) precoding matrices of:
{W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 },
wherein each of precoding matrices of {W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 } corresponds to each of {P a , P b , P c , . . . P d }.
8. The transceiver of claim 5 , wherein (v) corresponds to a spatial multiplexing rate.
9. A method for receiving signals at a receiver of a Multi-Input Multi-Output (MIMO) system, the method comprising:
receiving the signals transmitted from a transmitter using a plurality of antennas;
acquiring one or more streams from the received signals using a precoding matrix with a subset index (i) selected from a subset of a codebook, wherein the subset index (i) cyclically increases every (v) contiguous resource indices within a range from 0 to (N restrict )−1 wherein (v) is a predetermined integer value,
wherein the codebook includes (N) precoding matrices of {P 0 , P 1 , P 2 , . . . P (N)-1 }, each matrix having a codebook index (j), (j)=0, 1, . . . , (N)−1,
wherein the subset of the codebook includes (N restrict ) precoding matrices having matrix elements corresponding to one of ‘1’, ‘−1’, ‘j’ and represented as:
{P a , P b , P c , . . . P d }, wherein a, b, c, . . . , dε{0, 1, 2, . . . , (N)−1}, the number of a, b, c, . . . , d equals to the (N restrict ), and a<b<c< . . . <d,
wherein the subset index (i) of each (N restrict ) precoding matrix, selected from the (N) precoding matrices, is defined as 0, 1, . . . , (N restrict )−1 to correspond to each codebook index of the selected precoding matrices, and
wherein each of the subset indices of 0, 1, . . . , (N restrict )−1 corresponds in the order of a, b, c, . . . , d; and
decoding the one or more streams to acquire transmission information at a decoder.
10. The method of claim 9 , wherein the subset includes (N restrict ) precoding matrices of:
{W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 },
wherein each of precoding matrices of {W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 } corresponds to each of {P a , P b , P c , . . . P d }.
11. The method of claim 9 , wherein (i)=(s) mod (N restrict ), wherein ‘mod’ indicates a modulo operation, wherein (s) is a variable which increases per every (v) contiguous subcarriers.
12. The method of claim 9 , wherein (v) corresponds to a spatial multiplexing rate.
13. A transceiver for receiving signals in a Multi-Input Multi-Output (MIMO) system, the transceiver comprising:
a reception antenna for receiving the signals transmitted from a transmitter using a plurality of transmission antennas;
a MIMO decoder for acquiring one or more streams from the received signals using a precoding matrix with a subset index (i) selected from a subset of a codebook, wherein the subset index (i) cyclically increases every (v) contiguous resource indices within a range from 0 to (N restrict )−1 wherein (v) is a predetermined integer value,
wherein the codebook includes (N) precoding matrices of {P 0 , P 1 , P 2 , . . . , P (N)-1 }, each matrix having a codebook index (j), (j)=0, 1, . . . , (N)−1,
wherein the subset of the codebook includes (N restrict ) precoding matrices having matrix elements corresponding to one of ‘1’, ‘−1’, ‘j’ and ‘−j’ and represented as:
{P a , P b , P c , . . . P d }, wherein a, b, c, . . . , dε{0, 1, 2, . . . , (N)−1}, the number of a, b, c, . . . , d equals to the (N restrict ), and a<b<c< . . . <d,
wherein the subset index (i) of each of the (N restrict ) precoding matrix, selected from the (N) precoding matrices, is defined as 0, 1, . . . , (N restrict )−1 to correspond to each of the codebook index of the selected precoding matrices, and
wherein each of the subset indices of 0, 1, . . . , (N restrict )−1 corresponds in the order of a, b, c, . . . , d; and
a decoder for decoding the plurality of streams to acquire transmission information.
14. The method of claim 13 , wherein the subset includes (N restrict ) precoding matrices of:
{W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 },
wherein each of precoding matrices of {W 0 , W 1 , W 2 , . . . , W (Nrestrict)-1 } corresponds to each of {P a , P b , P c , . . . P d }.
15. The method of claim 13 , wherein (i)=(s) mod (N restrict ), wherein ‘mod’ indicates a modulo operation, wherein (s) is a variable which increases per every (v) contiguous subcarriers.
16. The method of claim 13 , wherein (v) corresponds to a spatial multiplexing rate.