Training sequences for very high throughput wireless communication

• US 8,155,138 B2
• Filed: 02/04/2009
• Issued: 04/10/2012
• Est. Priority Date: 08/19/2008
• Status: Active Grant

• Current Assignee: Sabic Innovative Plastics IP BV (Government of Saudi Arabia), Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: van Nee, Richard
• Primary Examiner(s): Mui, Gary
• Application Number:
  US12/365,802
• Publication Number:
  US 20100046358A1
• Time in Patent Office: 1,161 Days
• Field of Search: 370/442, 370/208, 370/203, 370/210, 370/334, 375/219, 375/229, 375/255, 375/316
• US Class Current: 370/442
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0017 in which a distinct code is applied, as a temporal sequence, to each frequency
• CPC Class Codes: H04L 5/0023 Time-frequency-space

Abstract

Methods and systems for communications that generate a plurality of spatial streams, wherein each of the spatial streams comprises a data packet with a training sequence; and multiply at least a portion of the training sequence in each of the spatial streams with a different spreading sequence. Methods and systems that receive a plurality of spatial streams, wherein each of the spatial streams comprises a data packet with a training sequence; multiply at least a portion of the training sequence in each of the spatial streams with a different spreading sequence; and decode the plurality of spatial streams based on the different spreading sequences.

Claims

1. An apparatus for communications, comprising:

means for receiving a plurality of spatial streams, wherein each of the spatial streams comprises a data packet having a training sequence, wherein at least a portion of the training sequence in each of the spatial streams is multiplied with a different spreading sequence; and

means for decoding the plurality of spatial streams based on the different spreading sequences.

2. The apparatus of claim 1 wherein each of the training sequences comprises a plurality of subcarriers, and wherein the subcarriers of said at least a portion of the training sequence in each of the spatial streams are multiplied with a different spreading sequence.

3. The apparatus of claim 1 wherein each of the spreading sequences comprises an orthogonal sequence.

4. The apparatus of claim 1 wherein one or more of the different spreading sequences comprise a cyclic delay.

5. The apparatus of claim 1 wherein each of the training sequences comprises k nonzero subcarriers.

6. The apparatus of claim 5 wherein each of the different spreading sequences comprises k values.

7. The apparatus of claim 5 wherein the spatial streams comprise m spatial streams, and wherein said at least a portion of the training sequence in each of the spatial streams are multiplied with a portion of an m×

k matrix comprising the different spreading sequences.

8. The apparatus of claim 7 wherein each of the training sequences comprises a plurality of subcarriers, and wherein the subcarriers of said at least a portion of the training sequence in each of the spatial streams are multiplied with said portion of the m×

k matrix comprising the different spreading sequences.

9. The apparatus of claim 8 wherein the matrix comprises a Hadamard matrix.

10. The apparatus of claim 5 said at least a portion of the training sequence in each of the spatial streams is multiplied with a portion of a Hadamard matrix comprising the different spreading sequences.

11. The apparatus of claim 5 wherein said at least a portion of the training sequence in each of the spatial streams is multiplied with a FFT matrix comprising the different spreading sequences.

12. The apparatus of claim 1 wherein the means for receiving is configured to receive each of the spatial streams via a different one of a plurality of antennas.

13. The apparatus of claim 1 further comprising means for using each of the training sequences to correct digital gain.