METHOD AND APPARATUS FOR TRANSMITTING REFERENCE SIGNALS IN UPLINK MULTIPLE INPUT MULTIPLE OUTPUT (MIMO) TRANSMISSION

• US 20120093120A1
• Filed: 06/28/2010
• Published: 04/19/2012
• Est. Priority Date: 06/26/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Ko, Hyun Soo, Noh, Min Seok, Chung, Jae Hoon, Han, Seung Hee, Lee, Moon II
• Granted Patent: US 8,842,623 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0671 using different delays between antennas
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 27/2636 with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 5/0016 Time-frequency-code
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path

Abstract

The present invention relates to a wireless communication system, and more particularly, to a method and an apparatus for transmitting reference signals in uplink MIMO transmission. According to one embodiment of the present invention, the method for transmitting uplink signals through a terminal in the wireless communication system comprises the steps of: receiving control information including the information on a cyclic shift and/or an orthogonal cover code; allocating the multiplexed reference signals onto an uplink subframe; and transmitting the subframe through a multi-antenna. When the uplink MIMO transmission is multiuser MIMO transmission, the reference signals of the terminal and the reference signals of other terminals can be multiplexed by using the orthogonal cover code.

Claims

1. A method for transmitting an uplink signal at a terminal in a wireless communication system, the method comprising:

receiving control information including information on Cyclic Shift (CS);

multiplexing reference signals for uplink Multiple Input Multiple Output (MIMO) transmission using at least one of the CS or an Orthogonal Cover Code (OCC);

allocating the multiplexed reference signals onto an uplink subframe; and

transmitting the subframe through multiple antennas,

wherein the reference signals of the terminal and reference signals of other terminals are multiplexed using the OCC when the uplink MIMO transmission is multiuser MIMO transmission.

2. The method according to claim 1, wherein values of the CS are allocated such that the spacing between CS values allocated to ranks 2 or more has a maximum value.

3. The method according to claim 1, wherein the reference signals are precoded reference signals in the case of spatial multiplexing multi-antenna transmission.

4. The method according to claim 1, wherein the information on CS includes information on allocation of two CS resources in the case of multi-antenna transmission in a transmission diversity scheme.

5. The method according to claim 1, wherein information on the OCC is implicitly acquired by the terminal from the information on CS.

6. The method according to claim 1, wherein information on the OCC is received by the terminal through L1/L2 control signaling or higher layer signaling.

7. The method according to claim 1, wherein the control information is included in a downlink control information format used for scheduling of physical uplink shared channels.

8. The method according to claim 1, wherein the reference signals are Demodulation Reference Signals (DMRSs).

9. A terminal transmitting an uplink signal in a wireless communication system, the terminal comprising:

a plurality of antennas;

a receiving module for receiving a signal from a Base Station (BS) through the plurality of antennas;

a transmission module for transmitting a signal to the BS through the plurality of antennas; and

a processor for controlling the terminal including the plurality of antennas, the receiving module and the transmission module,

wherein the processor is configured to;

receive control information including information on Cyclic Shift (CS) through the receiving module,

multiplex reference signals for uplink MIMO transmission using at least one of the CS or an orthogonal cover code (OCC),

allocate the multiplexed reference signals onto an uplink subframe, and transmit the subframe through the transmission module and the multiple antennas,

wherein the reference signals of the terminal and reference signals of other terminals are multiplexed using the OCC when the uplink MIMO transmission is multiuser MIMO transmission.

10. The terminal according to claim 9, wherein values of the CS are allocated such that the spacing between CS values allocated to two or more ranks has a maximum value.

11. The terminal according to claim 9, wherein the reference signals are precoded reference signals in the case of spatial multiplexing multi-antenna transmission.

12. The terminal according to claim 9, wherein the information on CS includes information on allocation of two CS resources in the case of multi-antenna transmission in a transmission diversity scheme.

13. The terminal according to claim 9, wherein information on the OCC is implicitly acquired by the terminal from the information on CS.

14. The terminal according to claim 9, wherein information on the OCC is received by the terminal through L1/L2 control signaling or higher layer signaling.

15. The terminal according to claim 9, wherein the control information is included in a downlink control information format used for scheduling of physical uplink shared channels.

16. The terminal according to claim 9, wherein the reference signals are Demodulation Reference Signals (DMRSs).