Spatial spreading in a multi-antenna communication system

• US 10,476,560 B2
• Filed: 10/09/2017
• Issued: 11/12/2019
• Est. Priority Date: 12/17/2003
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Walton, Jay Rodney, Zheng, Lizhong, Ketchum, John W., Wallace, Mark S., Howard, Steven J.
• Primary Examiner(s): Bocure, Tesfaldet
• Application Number:
  US15/728,407
• Publication Number:
  US 20180048362A1
• Time in Patent Office: 764 Days
• Field of Search: 455 99, 455101
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0669 using different channel coding between antennas space-time coding H04L1/0618
• CPC Class Codes: H04L 1/06 using space diversity

Abstract

Spatial spreading is performed in a multi-antenna system to randomize an “effective” channel observed by a receiving entity for each transmitted data symbol block. For a MIMO system, at a transmitting entity, data is processed (e.g., encoded, interleaved, and modulated) to obtain N_D data symbol blocks to be transmitted in N_M transmission spans, where N_D≥1 and N_M>1. The N_D blocks are partitioned into N_M data symbol subblocks, one subblock for each transmission span. A steering matrix is selected (e.g., in a deterministic or pseudo-random manner from among a set of L steering matrices, where L>1) for each subblock. Each data symbol subblock is spatially processed with the steering matrix selected for that subblock to obtain transmit symbols, which are further processed and transmitted via N_T transmit antennas in one transmission span. The N_D data symbol blocks are thus spatially processed with N_M steering matrices and observe an ensemble of channels.

Claims

1. A method of receiving a data transmission in a wireless multiple-input multiple-output MIMO communication system, comprising:

receiving, via a plurality of receive antennas, data symbols for at least two data symbol blocks, wherein for each of the at least two data symbol blocks, the data symbols are spatially processed with a plurality of steering matrices prior to transmission via a MIMO channel;

and

spatially processing the received data, based on the plurality of steering matrices, to obtain data symbol estimates for the at least two data symbol blocks.

2. The method of claim 1, wherein a steering matrix is selected for each transmission span, and wherein the spatially processing comprises spatially processing the received data symbols for each transmission span based on the steering matrix selected for the transmission span.

3. The method of claim 1, further comprising processing the data symbol estimates for the at least two data symbol blocks to obtain decoded data for the at least two data symbol blocks.

4. The method of claim 1, wherein the plurality of steering matrices are unitary matrices.

5. The method of claim 1, wherein each of the plurality of steering matrices comprises at least two columns.

6. The method of claim 1, wherein the plurality of steering matrices were selected in a deterministic manner.

7. The method of claim 1, wherein the plurality of steering matrices were selected in a pseudo-random manner.

8. The method of claim 1, wherein the plurality of steering matrices were selected in a permutated manner.

9. The method of claim 1, wherein receiving the data symbols comprises receiving an effective MIMO channel randomized by the plurality of steering matrices.

10. The method of claim 1, wherein each of the at least two data symbol blocks is separately coded.

11. An apparatus in a wireless multiple-input multiple-output MIMO communication system, comprising:

a plurality of receivers configured to receive data symbols for at least two data symbol blocks, wherein for each of the at least two data symbol blocks, the data symbols are spatially processed with a plurality of steering matrices prior to transmission via a MIMO channel; and

a spatial processor configured to spatially process the received data symbols with the channel response estimate to obtain data symbol estimates for the at least two data symbol blocks.

12. The apparatus of claim 11, wherein a steering matrix is selected for each transmission span;

wherein the spatial processor is further configured to spatially process the received data symbols for each transmission span based on the steering matrix selected for the transmission span.

13. The apparatus of claim 11, further comprising a data processor configured to process the data symbol estimates for the at least two data symbol blocks to obtain decoded data for the at least two data symbol blocks.

14. The apparatus of claim 11, wherein the plurality of steering matrices are unitary matrices.

15. The apparatus of claim 11, wherein each of the plurality of steering matrices comprises at least two columns.

16. The apparatus of claim 11, wherein the plurality of steering matrices were selected in a deterministic manner.

17. The apparatus of claim 11, wherein the plurality of steering matrices were selected in a pseudo-random manner.

18. The apparatus of claim 11, wherein the plurality of steering matrices were selected in a permutated manner.

19. The apparatus of claim 11, wherein the plurality of receivers is further configured to receive an effective MIMO channel randomized by the plurality of steering matrices.

20. The apparatus of claim 11, wherein each of the at least two data symbol blocks is separately coded.