Method and apparatus for transceiving a precoded signal in a multiple antenna supported wireless communication system
The present invention relates to a method for transmitting a signal from a transmitter to a receiver through N number of transmitting antennas (where N≧2), comprising: selecting a first and a second matrix from a first and a second codebook related to a first and a second precoding matrix indicator (PMI), respectively, and determining a precoding matrix on the basis of the first and second matrix; performing precoding by using the determined precoding matrix for L number of layers (where 1≦L≦N) to which a signal to be transmitted to the receiver is mapped; and transmitting the precoded signal to the receiver through the N number of transmitting antennas. Here, the first codebook includes one or more diagonal matrices having an N×N size, non-zero elements in the diagonal matrix has a predetermined phase value, and the second codebook includes one or more matrices having an N×L size.
1. A method for transmitting a signal to a receiver through N (N≧2) transmission antennas in a transmitter, comprising:
selecting a first precoding matrix from a first codebook associated with a first Precoding Matrix Indicator (PMI);
selecting a second precoding matrix from a second codebook associated with a second PMI;
determining a precoding matrix by a product of the first precoding matrix and the second precoding matrix;
performing precoding using the determined precoding matrix with respect to L (1≦L≦N) layers to which a signal to be transmitted to the receiver is mapped; and
transmitting the precoded signal to the receiver through the N transmission antennas,
wherein the first precoding matrix is a phase matrix having a N×N size, and elements other than 0 in the phase diagonal matrix have prescribed phase values,
wherein the second precoding matrix is a matrix having a N×L size.
2. The method of claim 1 , wherein, when the number L of the layers is a specific number or more, the first precoding matrix is an identity matrix which has values of 1 for the elements other than 0.
3. The method of claim 2 , wherein the specific number of the layers is 2 or more.
4. The method of claim 1 , wherein the first codebook includes a plurality of diagonal matrices and one of the plurality of diagonal matrices is an identity matrix.
5. The method of claim 1 ,
wherein elements other than 0 in the phase diagonal matrix are composed of one column vector of a prescribed matrix, and
wherein the prescribed matrix is one of an N-point Discrete Fourier Transform (DFT) matrix, a matrix included in a single codebook, and a matrix determined by a combination of multiple codebooks.
6. The method of claim 1 ,
wherein the phase diagonal matrix is determined by a product of a first diagonal matrix of N×N size and a second diagonal matrix of N×N size,
wherein elements other than 0 of the first diagonal matrix are composed of a column vector of an N-point DFT matrix or a vector concatenating column vector of an N/2-point DFT matrix, and
wherein elements other than 0 of the second diagonal matrix are composed of one column vector of the N-point DFT matrix or a repetitive form of a prescribed phase value.
7. A method for receiving a signal from a transmitter in a receiver, comprising:
receiving the signal transmitted through N (N≧2) transmission antennas of the transmitter; and
processing the received signal,
wherein the received signal is a signal upon which precoding has been performed using a precoding matrix with respect to L (1≦L≦N) layers to which a signal to be transmitted to the receiver from the transmitter is mapped,
wherein the precoding matrix is determined by a product of a first precoding matrix and a second precoding matrix,
wherein the first precoding matrix is selected from a first codebook associated with a first Precoding Matrix Indicator (PMI) and the second precoding matrix is selected from a second codebook associated with a second PMI,
wherein the first precoding matrix is a phase matrix having a N×N size, and elements other than 0 in the phase diagonal matrix have prescribed phase values, and
wherein the second precoding matrix is a matrix having a N×L size.
8. The method of claim 7 , wherein, when the number L of the layers is a specific number or more, the first precoding matrix is an identity matrix which has values of 1 for the elements other than 0.
9. The method of claim 8 , wherein the specific number is 2 or more.
10. The method of claim 7 , wherein the first codebook includes a plurality of diagonal matrices and one of the plurality of diagonal matrices is an identity matrix.
11. The method of claim 7 ,
wherein elements other than 0 in the phase diagonal matrix are composed of one column vector of a prescribed matrix, and
wherein the prescribed matrix is one of an N-point Discrete Fourier Transform (DFT) matrix, a matrix included in a single codebook, and a matrix determined by a combination of multiple codebooks.
12. The method of claim 7 ,
wherein the phase diagonal matrix is determined by a product of a first diagonal matrix of N×N size and a second diagonal matrix of N×N size,
wherein elements other than 0 of the first diagonal matrix are composed of one of one column vector of an N-point DFT matrix or a vector concatenating column vector of an N/2-point DFT matrix, and
wherein elements other than 0 of the second diagonal matrix are composed of one column vector of the N-point DFT matrix or a repetitive form of a prescribed phase value.
13. A transmit device for transmitting a precoded signal, the transmit device comprising:
a transmitter configured to transmit a signal to a receiver;
receiver configured to receive a signal from the receiver;
a memory configured to store first and second codebooks,
N (N≧2) transmission antennas; and
a processor configured to the transmitter,
wherein the processor is further configured to
select a first precoding matrix from a first codebook associated with a first Precoding Matrix Indicator (PMI);
select a second precoding matrix from a second codebook associated with a second PMI;
determine a precoding matrix by a product of the first precoding matrix and the second precoding matrix;
perform precoding using the determined precoding matrix with respect to L (1≦L≦N) layers to which a signal to be transmitted to the receiver is mapped; and
transmit the precoded signal to the receiver through the N transmission antennas,
wherein the first precoding matrix is a phase matrix having a N×N size, and elements other than 0 in the phase diagonal matrix have prescribed phase values,
wherein the second precoding matrix is a matrix having a N×L size.
14. A receive device for receiving a precoded signal, the receive device comprising:
a transmitter configured to transmit a signal to a transmitter;
a receiver configured to receive a signal from the transmitter;
a memory configured to store first and second codebooks,
one or more antennas; and
a processor configured to control the receiver,
wherein the processor is further configured to
receive the signal transmitted through N (N≧ 2 ) transmission antennas of the transmitter; and
process the received signal,
wherein the received signal is a signal upon which precoding has been performed using a precoding matrix with respect to L (1≦L≦N) layers to which a signal to be transmitted to the receiver from the transmitter is mapped,
wherein the precoding matrix is determined by a product of a first precoding matrix and a second precoding matrix,
wherein the first precoding matrix is selected from a first codebook associated with a first Precoding Matrix Indicator (PMI) and the second precoding matrix is selected from a second codebook associated with a second PMI,
wherein the first precoding matrix is a phase matrix having a N×N size, and elements other than 0 in the phase diagonal matrix have prescribed phase values, and
wherein the second precoding matrix is a matrix having a N×L size.