METHOD FOR MULTI-ANTENNA UPLINK TRANSMISSION

• US 20100279621A1
• Filed: 04/30/2009
• Published: 11/04/2010
• Est. Priority Date: 04/30/2009
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Stewart, Kenneth, Zhuang, Xiangyang, Frank, Colin, BROWN, Tyler, Krishnamurthy, Sandeep
• Granted Patent: US 9,287,957 B2
• Time in Patent Office: Days
• US Class Current: 455/67.11
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0628 Diversity capabilities
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0029 Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling power control H04W52/04

Abstract

A method (300) and apparatus (106) for transmitting information based on a relationship between a first channel and a second channel is disclosed. The method can include taking (302) a first channel measurement corresponding to a first antenna of a wireless terminal and taking (304) a second channel measurement corresponding to a second antenna of the wireless terminal. The method can include determining (306) a relationship between the first channel and the second channel based on the first channel measurement and based on the second channel measurement. The method can include transmitting (310) information related to an uplink transmission where the information can be based on the relationship.

Claims

1. A method in a wireless terminal, the method comprising:

taking a first channel measurement corresponding to a first antenna of the wireless terminal;

taking a second channel measurement corresponding to a second antenna of the wireless terminal;

determining a relationship between the first channel and the second channel based on the first channel measurement and based on the second channel measurement; and

transmitting information related to a multi-antenna uplink transmission wherein the information is based on the relationship.

2. The method according to claim 1, wherein the relationship is based on a correlation between the first channel and the second channel based on the first channel measurement and based on the second channel measurement.

3. The method according to claim 1, wherein the relationship is based on a ratio of a gain of the first channel to a gain of the second channel based on the first channel measurement and based on the second channel measurement.

4. The method according to claim 1, wherein the relationship is based on a difference between the path loss corresponding to the first antenna of the wireless terminal and the path loss corresponding to the second antenna of the wireless terminal.

5. The method according to claim 1,

wherein taking a first channel measurement comprises taking a first reference signal receive power measurement of a first channel corresponding to a first antenna, and

wherein taking a second channel measurement comprises taking a second reference signal receive power measurement of a second channel corresponding to a second antenna.

6. The method according to claim 1, wherein the information related to a multi-antenna uplink transmission comprises the relationship between the first channel and the second channel.

7. The method according to claim 1, wherein the information related to a multi-antenna uplink transmission corresponds to a preference for which antenna should be used for an uplink transmission.

8. The method according to claim 1, wherein the information related to a multi-antenna uplink transmission corresponds to the difference between a first power headroom of the power amplifier associated with the first antenna and a second power headroom of the power amplifier associated with the second antenna.

9. The method according to claim 1, wherein transmitting information related to a multi-antenna uplink transmission is triggered by comparing the relationship between the first channel and the second channel with a predefined value.

10. The method according to claim 1, wherein the information related to a multi-antenna uplink transmission includes a preference for a transmission mode selected from a set of transmission modes including at least two of:

a single antenna transmission mode, a multi-antenna transmission mode, an open loop transmission mode, a closed loop transmission mode, a direct layer mapping transmission mode, and a mixed layer mapping transmission mode.

11. A method in a base station, the method comprising:

receiving information related to a multi-antenna uplink transmission wherein the received information is based on channel measurements made by a wireless terminal, the channel measurements corresponding to a first antenna of the wireless terminal and a second antenna of the wireless terminal;

selecting a multi-antenna transmission mode for uplink transmission from the wireless terminal based on the received information; and

sending an indication of the selected a multi-antenna transmission mode to the wireless terminal.

12. The method according to claim 11, wherein the received information is based on a relationship between at least a first measured channel corresponding to a first antenna at the wireless terminal and a second measured channel corresponding to a second antenna at the wireless terminal.

13. The method according to claim 11, wherein the received information is based on a ratio of the gain of a first channel corresponding to a first antenna at the wireless terminal and the gain of a second channel corresponding to a second antenna at the wireless terminal.

14. The method according to claim 11, wherein the selected multi-antenna transmission mode comprises an instruction of a configuration of a reference signal transmission by the wireless terminal at each antenna.

15. The method according to claim 14, wherein the configuration comprises at least one of properties including pattern, power, and frequency of a reference signal transmission.

16. The method according to claim 11, wherein the selected multi-antenna transmission mode includes a set of possible precoding matrices used by the wireless terminal when transmitting on the first antenna and the second antenna.

17. A wireless terminal comprising:

a first antenna;

a second antenna;

a transceiver coupled to the first antenna and coupled to the second antenna;

a controller coupled to the transceiver, the controller configured to control operations of the wireless terminal;

a channel measurement module coupled to the first antenna and coupled to the second antenna, the channel measurement module configured to take a first channel measurement corresponding to the first antenna and configured to take a second channel measurement corresponding to the second antenna; and

a channel relationship determination module coupled to the controller, the channel relationship determination module configured to determine a relationship between the first channel and the second channel based on the first channel measurement and based on the second channel measurement,

wherein the transceiver is configured to transmit information related to a multi-antenna uplink transmission wherein the information is based on the relationship.

18. The wireless terminal according to claim 17, wherein the relationship is based on a correlation between the first channel and the second channel based on the first channel measurement and based on the second channel measurement.

19. The wireless terminal according to claim 17, wherein the relationship is based on a ratio of a gain of the first channel to a gain of the second channel based on the first channel measurement and based on the second channel measurement.

20. The wireless terminal according to claim 17,

wherein the channel measurement module is configured to take a first channel measurement by taking a first reference signal receive power measurement of a first channel corresponding to a first antenna, and

wherein the channel measurement module is configured to take a first channel measurement by taking a second reference signal receive power measurement of a second channel corresponding to a second antenna.