Method and System for Precoding Data

1. A non-transitory tangible computer-readable medium having stored thereon, a computer program comprising at least one code section for distributing data, the at least one code section being executable by a machine for causing the machine to perform the following: receiving at least one reference signal from a transmitting device; deriving a rank indication, a codebook index n 1 in a first codebook C 1 , and codebook indices k 1 and k 2 in a second codebook C 2 based on the at least one reference signal; sending the rank indication, the codebook index n 1 in the first codebook C 1 , and the codebook indices k 1 and k 2 in the second codebook C 2 to the transmitting device; and receiving data precoded by a first precoder from the transmitting device; wherein the first precoder comprises a second precoder and a third precoder, the second precoder is determined based on the indices n 1 and k 1 , and the third precoder is determined based on the indices n 1 and k 2 .

2. The non-transitory tangible computer-readable medium according to claim 1 , wherein the second precoder is a wideband precoder and the third precoder is a subband precoder.

3. The non-transitory tangible computer-readable according to claim 1 , wherein the first codebook C 1 and the second codebook C 2 are configured in both the transmitting device and the machine.

4. The non-transitory tangible computer-readable medium according to claim 1 , wherein sending the rank indication, the codebook index n 1 in the first codebook C 1 , and the codebook indices k 1 and k 2 in the second codebook C 2 to the transmitting device, further comprises: sending a first message that contains the rank indication; sending a second message that contains the indices n 1 and k 1 ; and sending a third message that contains the index k 2 .

5. The non-transitory tangible computer-readable medium according to claim 1 , wherein the machine is one of the following: a mobile device, a cellular telephone, a wireless enabled personal digital assistant and a wireless enabled laptop computer.

6. A non-transitory tangible computer-readable medium having stored thereon, a computer program comprising at least one code section for distributing data, the at least one code section being executable by a machine for causing the machine to perform the following: receiving a rank indication, a codebook index n 1 in a first codebook C 1 , and codebook indices k 1 and k 2 in a second codebook C 2 from a receiving device; determining a first precoder based on the rank indication, the indices n 1 , k 1 and k 2 ; precoding data to be sent to the receiving device by the first precoder; and sending the precoded data to the receiving device; wherein the first precoder comprises a second precoder and a third precoder, the second precoder is determined based on the indices n 1 and k 1 , and the third precoder is determined based on the indices n 1 and k 2 .

7. The non-transitory tangible computer-readable medium according to claim 6 , wherein the second precoder is a wideband precoder and the third precoder is a subband precoder.

8. The non-transitory tangible computer-readable medium according to claim 6 , wherein determining the second precoder, comprises: determining a matrix W n 1 (1) based on the index n 1 in the first codebook C 1 ; determining a matrix W k 1 (2) based on the index k 1 in the second codebook C 2 ; and determining the second precoder W 1 based on W 1 =W n 1 (1) W k 1 (2) ; and wherein determining the third precoder, further comprises: determining a matrix W n 1 (1) based on the index n 1 in the first codebook C 1 ; determining a matrix W k 2 (2) based on the index k 2 in the second codebook C 2 ; and determining the third precoder W 2 based on W 2 =W n 1 (1) W k 2 (2) .

9. The non-transitory tangible computer-readable medium according to claim 6 , wherein determining the second precoder, further comprises: determining a matrix W n 1 (1) based on the index n 1 in the first codebook C 1 ; determining a matrix W k 1 (2) based on the index k 1 in the second codebook C 2 ; and determining the second precoder W 1 based on W 1 =W k 1 (2) W n 1 (1) ; and wherein determining the third precoder, further comprises: determining a matrix W n 1 (1) based on the index n 1 in the first codebook C 1 ; determining a matrix W k 2 (2) based on the index k 2 in the second codebook C 2 ; and determining the third precoder W 2 based on W 2 =W k 2 (2) W n 1 (1) .

10. The non-transitory tangible computer-readable medium according to claim 6 , wherein the first codebook C 1 and the second codebook C 2 are configured in both the machine and the receiving device.

11. The non-transitory tangible computer-readable medium according to claim 6 , wherein the machine is a base station or an access point.