Systems and methods for enhanced MIMO operation

• US 9,698,887 B2
• Filed: 03/06/2014
• Issued: 07/04/2017
• Est. Priority Date: 03/08/2013
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Geirhofer, Stefan, Gaal, Peter, Chen, Wanshi, Xu, Hao
• Primary Examiner(s): Malek, Leila
• Application Number:
  US14/199,743
• Publication Number:
  US 20140254701A1
• Time in Patent Office: 1,216 Days
• Field of Search: 370329, 370252, 375267, 375299, 375316, 375340, 375347
• CPC Class Codes: H04B 7/0469 taking special antenna structures, e.g. cross polarized antennas into account
• CPC Class Codes: H04B 7/0478 Special codebook structures directed to feedback optimisation
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/0647 Variable feedback rate
• CPC Class Codes: H04B 7/0695 using beam selection

Abstract

A method for channel state information (CSI) reporting by a wireless communication device is described. The method includes determining a codebook for a CSI report corresponding to four transmit antenna (4Tx) transmissions from a base station. The codebook has a dual codebook structure. The method also includes generating the CSI report using the codebook. The method further includes transmitting the CSI report to a base station.

Claims

1. A method for channel state information (CSI) reporting by a base station, comprising:

determining a codebook used by a wireless communication device for a CSI report corresponding to four transmit antenna (4Tx) transmissions from the base station, wherein the codebook has a dual codebook structure comprising a block-diagonal grid of beams structure W=W₁·

W₂, wherein W₁ is a first matrix that is reported on a wideband basis, wherein W₂ is a second matrix that is reported on a subband basis;

receiving the CSI report as a type 5 report in physical uplink control channel (PUCCH) mode 1-1, submode 1, wherein the type 5 report uses 1 bit to represent a rank indicator for maximum 2-layer spatial multiplexing and 2 bits to represent the rank indicator for maximum 4-layer spatial multiplexing; and

decoding the CSI report using the codebook.

2. The method of claim 1, wherein the first matrix (W₁) defines a grid of beams for each polarization, and wherein the second matrix (W₂) performs beam selection within a beam group and co-phasing.

3. The method of claim 1, wherein the codebook is determined based on at least one of a grid of beam resolution, a size of beam groups, an overlap between beam groups, and a co-phasing accuracy.

4. The method of claim 3, wherein each parameter used to generate the codebook is individually adaptable.

5. The method of claim 1, further comprising signaling the codebook using signaling based on at least one of explicit bits, dynamic parameters and semi-static parameters.

6. The method of claim 1, wherein the wireless communication device determines which of multiple configured codebooks should be used for CSI reporting.

7. The method of claim 1, wherein multiple user channel quality indicator hypotheses remain separate from codebook adaptation.

8. The method of claim 1, wherein multiple user channel quality indicator hypotheses follow codebook adaptation.

9. The method of claim 1, further comprising performing codebook subsampling to meet an 11 bit payload constraint for the CSI report.

10. A base station for channel state information (CSI) reporting, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to;

determine a codebook used by a wireless communication device for a CSI report corresponding to four transmit antenna (4Tx) transmissions from the base station, wherein the codebook has a dual codebook structure comprising a block-diagonal grid of beams structure W=W₁·

W₂, wherein W₁ is a first matrix that is resorted on a wideband basis wherein W₂ is a second matrix that is reported on a subband basis;

receive the CSI report as a type 5 report in physical uplink control channel (PUCCH) mode 1-1, submode 1, wherein the type 5 report uses 1 bit to represent a rank indicator for maximum 2-layer spatial multiplexing and 2 bits to represent the rank indicator for maximum 4-layer spatial multiplexing; and

decoding the CSI report using the codebook.

11. The base station of claim 10, wherein the codebook is determined based on at least one of a grid of beam resolution, a size of beam groups, an overlap between beam groups, and a co-phasing accuracy.

12. The base station of claim 11, wherein each parameter used to generate the codebook is individually adaptable.

13. The base station of claim 10, further comprising instructions executable to signal the codebook using signaling based on at least one of explicit bits, dynamic parameters and semi-static parameters.

14. The base station of claim 10, wherein the wireless communication device determines which of multiple configured codebooks should be used for CSI reporting.

15. A base station for channel state information (CSI) reporting, comprising:

means for determining a codebook used by a wireless communication device for a CSI report corresponding to four transmit antenna (4Tx) transmissions from the base station, wherein the codebook has a dual codebook structure comprising a block-diagonal grid of beams structure W=W₁·

W₂, wherein W₁ is a first matrix that is resorted on a wideband basis wherein W₂ is a second matrix that is reported on a subband basis;

means for receiving the CSI report as a type 5 report in physical uplink control channel (PUCCH) mode 1-1, submode 1, wherein the type 5 report uses 1 bit to represent a rank indicator for maximum 2-layer spatial multiplexing and 2 bits to represent the rank indicator for maximum 4-layer spatial multiplexing; and

means for decoding the CSI report using the codebook.

16. A computer-program product for channel state information (CSI) reporting, the computer-program product comprising a non-transitory computer-readable medium having instructions thereon, the instructions comprising:

code for causing a base station to determine a codebook used by a wireless communication device for a CSI report corresponding to four transmit antenna (4Tx) transmissions from the base station, wherein the codebook has a dual codebook structure comprising a block-diagonal grid of beams structure W=W₁·

W₂, wherein W₁ is a first matrix that is resorted on a wideband basis wherein W₂ is a second matrix that is reported on a subband basis;

code for causing the base station to receive the CSI report as a type 5 report in physical uplink control channel (PUCCH) mode 1-1, submode 1, wherein the type 5 report uses 1 bit to represent a rank indicator for maximum 2-layer spatial multiplexing and 2 bits to represent the rank indicator for maximum 4-layer spatial multiplexing;

code for causing the base station to decode the CSI report using the codebook.