Method and apparatus for multiple input multiple output (MIMO) transmit beamforming

• US 8,428,177 B2
• Filed: 10/13/2009
• Issued: 04/23/2013
• Est. Priority Date: 02/25/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Tsai, Jiann-An, Pi, Zhouyue
• Primary Examiner(s): Ahn, Sam K
• Assistant Examiner(s): Wong, Linda
• Application Number:
  US12/587,708
• Publication Number:
  US 20100215112A1
• Time in Patent Office: 1,288 Days
• Field of Search: 375/219, 375/220, 375/222, 37524026-24027, 375284-285, 375/295, 375/296, 375/316, 375/221, 375/259, 375/299, 375260-269, 375/358, 375/346, 375/395, 370/319, 370208-209, 370343-344, 455/69, 455/67.11, 455/67.13, 455/63.1, 455/101, 455/522
• US Class Current: 375/295
• CPC Class Codes: H04B 7/0408 using two or more beams, i.e. beam diversity
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0465 taking power constraints at power amplifier or emission constraints, e.g. constant modulus, into account
• 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 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection

Abstract

A wireless communications network is provided. The wireless communications network comprises a plurality of base stations. Each one of said base stations is capable of wireless communications with a plurality of subscriber stations. At least one of said plurality of base stations comprises a processor configured to select a codeword from a codebook and precode data with the selected codeword, and a transmitter configured to transmit the precoded data. Rank 1 of the codebook is selected from the following algorithm:

Codebook Matrix Index (CMI) Base Matrix Rank 1 1 V8(:, :, 3) V8(:, 1, 3) 2 V8(:, 2, 3) 3 V8(:, 3, 3) 4 V8(:, 4, 3) 5 V8(:, 5, 3) 6 V8(:, 6, 3) 7 V8(:, 7, 3) 8 V8(:, 8, 3) 9 V8(:, 9, 3) 10 V8(:, 10, 3) 11 V8(:, 11, 3) 12 V8(:, 12, 3) 13 V8(:, 13, 3) 14 V8(:, 14, 3) 15 V8(:, 15, 3) 16 V8(:, 16, 3).

Claims

1. A base station including a multiple antenna array for wireless communication, comprising:

a codebook;

a processor configured to select a codeword from the codebook and to code data with the selected codeword; and

a transmitter configured to transmit the coded data,

wherein codewords in the codebook are based on values shown in the following table;

2. The base station of claim 1, wherein the values in the table are obtained based on the following equation:

3. The base station of claim 2, wherein θ

_k is given by the following equation;

4. The base station of claim 1, wherein the codebook is a 4-bit codebook.

5. The base station of claim 1, wherein the table includes real and imaginary values for the second to eighth antennas (c2˜

c8) of the multiple antenna array for each CMI.

6. A base station including a multiple antenna array for wireless communication, comprising:

a codebook;

a processor configured to select a codeword from the codebook and to code data with the selected codeword; and

a transmitter configured to transmit the coded data,

wherein codewords in the codebook are based on the following equation;

7. The base station of claim 6, wherein θ

_k is given by the following equation;

8. The base station of claim 6, wherein the codebook is a 4-bit codebook.

9. The base station of claim 6, wherein the codewords in the codebook account for real and imaginary components of one or more antennas of the multiple antenna array.

10. A method for coding data in a base station including a multiple antenna array for wireless communication, the method comprising:

selecting a codeword from a codebook;

coding data with the selected codeword; and

transmitting the coded data,

wherein codewords in the codebook are based on values shown in the following table;

11. The method of claim 10, wherein the values in the table are obtained based on the following equation:

12. The method of claim 11, wherein θ

_k is given by the following equation;

13. The method of claim 12, wherein the codebook is a 4-bit codebook.

14. The method of claim 13, wherein the table includes real and imaginary values for the second to eighth antennas (c2˜

c8) of the multiple antenna array for each CMI.

15. A method for coding data in a base station including a multiple antenna array for wireless communication, comprising:

selecting a codeword from a codebook;

coding data with the selected codeword; and

transmitting the coded data,

wherein codewords in the codebook are based on the following equation;

16. The method of claim 15, wherein θ

_k is given by the following equation;

17. The method of claim 15, wherein the codebook is a 4-bit codebook.

18. The method of claim 15, wherein the codewords in the codebook account for real and imaginary components of one or more antennas of the multiple antenna array.

19. A data structure stored on a non-transitory computer readable medium for coding data in a base station including a multiple antenna array for wireless communication, comprising:

a codebook comprising a plurality of codewords configured to be selected by a processor in the base station for coding data,

wherein the codewords in the codebook are based on values shown in the following table;

20. The data structure of claim 19, wherein the values in the table are obtained based on the following equation:

21. The data structure of claim 20, wherein θ

_k is given by the following equation;

22. The data structure of claim 19, wherein the codebook is a 4-bit codebook.

23. The data structure of claim 19, wherein the table includes real and imaginary values for the second to eighth antennas (c2˜

c8) of the multiple antenna array for each CMI.