METHOD, APPARATUS AND SYSTEM FOR IMPLEMENTING MULTI-USER VIRTUAL MULTIPLE-INPUT MULTIPLE-OUTPUT

• US 20080032746A1
• Filed: 08/07/2007
• Published: 02/07/2008
• Est. Priority Date: 08/07/2006
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Pan, Kyle Jung-Lin, Olesen, Robert Lind, Grieco, Donald M.
• Granted Patent: US 8,305,956 B2
• Time in Patent Office: Days
• US Class Current: 455/562.1
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0669 using different channel coding between antennas space-time coding H04L1/0618
• CPC Class Codes: H04B 7/0671 using different delays between antennas

Abstract

A method and system for implementing multi-user virtual multiple-input multiple-output (MIMO) techniques for wireless transmit/receive units (WTRUs) having one or more antennas are disclosed. The system includes a base station and at least one WTRU having at least two antennas. The number of antennas of the base station is not less than the number of antennas of any of the WTRUs. The base station generates a channel matrix for the WTRUs and processes received signals from the WTRUs based on a measurement of the channel matrix. The WTRUs may perform transmit precoding or eigen-beamforming using the channel matrix information. The WTRUs may also perform transmit diversity.

Claims

1. In a wireless communication system including a base station and a plurality of wireless transmit/receive units (WTRUs), the base station including a plurality of antennas, and at least one of said WTRUs including at least two antennas wherein the number of antennas of the base station is not less than the number of antennas of any of the WTRUs, a method for implementing multi-user virtual multiple-input multiple-output (MIMO), the method comprising:

the base station generating a channel matrix for the WTRUs; and

the base station processing received signals from the WTRUs using the channel matrix.

2. The method of claim 1 wherein the WTRUs perform a transmit precoding using the channel matrix.

3. The method of claim 1 wherein the WTRUs perform eigen-beamforming using the channel matrix.

4. The method of claim 1 wherein the WTRUs perform transmit diversity.

5. The method of claim 4 wherein the WTRUs perform at least one of space time block coding (STBC), space frequency block coding (SFBC), and cyclic delay diversity (CDD).

6. The method of claim 1 wherein at least one of the WTRUs supports only one spatial stream and the rest of the WTRUs support at least two spatial streams.

7. The method of claim 1 wherein the base station and the WTRUs implement single carrier frequency division multiple access (SC-FDMA).

8. The method of claim 1 wherein the base station and the WTRUs implement orthogonal frequency division multiple access (OFDMA).

9. The method of claim 1 wherein the base station and the WTRUs implement multi-carrier orthogonal frequency division multiple access (MC-OFDMA).

10. A wireless communication system for implementing multi-user virtual multiple-input multiple-output (MIMO), the system comprising:

a plurality of wireless transmit/receive units (WTRUs), at least one WTRU having at least two antennas; and

a base station comprising;

a plurality of antennas, the number of the base station antennas being not less than the number of antennas of any of the WTRUs;

a channel estimator for generating a channel matrix for the WTRUs; and

a receiver for processing signals transmitted from the WTRUs using the channel matrix.

11. The system of claim 10 wherein the WTRUs perform transmit precoding using the channel matrix.

12. The system of claim 10 wherein the WTRUs perform eigen-beamforming using the channel matrix.

13. The system of claim 10 wherein the WTRUs perform transmit diversity.

14. The system of claim 13 wherein the WTRUs perform at least one of space time block coding (STBC) and space frequency block coding (SFBC).

15. The system of claim 10 wherein at least one of the WTRUs supports only one spatial stream and the rest of the WTRUs support at least two spatial streams.

16. The system of claim 10 wherein the base station and the WTRUs implement single carrier frequency division multiple access (SC-FDMA).

17. The system of claim 10 wherein the base station and the WTRUs implement orthogonal frequency division multiple access (OFDMA).

18. The system of claim 10 wherein the base station and the WTRUs implement multi-carrier orthogonal frequency division multiple access (MC-OFDMA).

19. The system of claim 10 wherein the WTRUs selectively transmit the signals using one of a single stream MIMO and a multi-stream MIMO.

20. A base station for implementing multi-user virtual multiple-input multiple-output (MIMO) for a plurality of wireless transmit/receive units (WTRUs), at least one WTRU having at least two antennas, the base station comprising:

a plurality of antennas, the number of the base station antennas being not less than the number of antennas of any of the WTRUs;

a channel estimator for generating a channel matrix for the WTRUs; and

a receiver for processing signals from the WTRUs using the channel matrix.

21. The base station of claim 20 wherein the receiver is configured to process the signals that are processed for transmit precoding by the WTRUs using the channel matrix.

22. The base station of claim 20 wherein the receiver is configured to process the signals that are processed for eigen-beamforming by the WTRUs using the channel matrix.

23. The base station of claim 20 wherein the receiver is configured to process the signals that are processed for transmit diversity by the WTRUs.

24. The base station of claim 23 wherein the receiver is configured to process the signals that are processed for at least one of space time block coding (STBC), space frequency block coding (SFBC), and cyclic delay diversity (CDD) by the WTRUs.

25. The base station of claim 20 wherein at least one of the WTRUs supports only one spatial stream and the rest of the WTRUs support at least two spatial streams.

26. The base station of claim 20 wherein the base station implements single carrier frequency division multiple access (SC-FDMA).

27. The base station of claim 20 wherein the base station implements orthogonal frequency division multiple access (OFDMA).

28. The base station of claim 20 wherein the base station implements multi-carrier orthogonal frequency division multiple access (MC-OFDMA).