METHOD FOR PERFORMING RETRANSMISSION IN MIMO WIRELESS COMMUNICATION SYSTEM AND APPARATUS THEREFOR

• US 20120269137A1
• Filed: 08/02/2010
• Published: 10/25/2012
• Est. Priority Date: 08/20/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kang, Byeong Woo, Roh, Dong Wook, Noh, Yu Jin, Kim, Bong Hoe, Lee, Dae Won
• Granted Patent: US 9,042,314 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0404 the mobile station comprising multiple antennas, e.g. to provide uplink diversity
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network

Abstract

A method for performing retransmission at a user equipment of a MIMO wireless communication system is disclosed. The method comprises transmitting multiple transport blocks to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator; receiving ACK/NACK (Acknowledgement/Negative-ACK) responses corresponding to the respective transport blocks and uplink grant information, which includes a second new data indicator, from the base station; and performing new transmission or retransmission for the multiple transport blocks in one transport block unit for a transmission unit time in accordance with the ACK/NACK responses and the second new data indicator, if transport rank is reduced to 1.

Claims

1. A method for performing retransmission at a user equipment of a MIMO wireless communication system, the method comprising:

transmitting multiple transport blocks to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator;

receiving ACK/NACK (Acknowledgement/Negative-ACK) responses corresponding to the respective transport blocks and uplink grant information, which includes a second new data indicator, from the base station; and

performing new transmission or retransmission for the multiple transport blocks in one transport block unit for a transmission unit time in accordance with the ACK/NACK responses and the second new data indicator, if transport rank is reduced to 1.

2. The method of claim 1, wherein, if the ACK/NACK responses are all ACK responses and the second new data indicator has a value different from that of the first new data indicator, the step of performing new transmission or retransmission further includes flushing a buffer corresponding to one of the multiple transport blocks, which is intended for new transmission.

3. The method of claim 1, wherein, if the ACK/NACK responses includes at least one ACK response and at least one NACK response and the second new data indicator has the same value as that of the first new data indicator, the step of performing new transmission or retransmission further includes maintaining a buffer corresponding to the transport block that has received the NACK response.

4. The method of claim 1, wherein, if the ACK/NACK responses are all NACK responses and the second new data indicator has the same value that of the first new data indicator, the step of performing new transmission or retransmission further includes maintaining buffers corresponding to the respective transport blocks.

5. A method for performing retransmission at a user equipment of a MIMO wireless communication system, the method comprising:

transmitting multiple transport blocks to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator;

receiving ACK/NACK (Acknowledgement/Negative-ACK) responses corresponding to the respective transport blocks and uplink grant information, which includes a second new data indicator, from the base station; and

performing new transmission or retransmission for the multiple transport blocks in one transport block unit for a transmission unit time in accordance with the ACK/NACK responses and the second new data indicator, if transport rank is maintained.

6. The method of claim 5, wherein, if the ACK/NACK responses are all ACK responses and the second new data indicator has a value different from that of the first new data indicator, the step of performing new transmission or retransmission further includes flushing buffers corresponding to the multiple transport blocks.

7. The method of claim 5, wherein, if the ACK/NACK responses includes at least one ACK response and at least one NACK response and the second new data indicator has the same value as that of the first new data indicator, the step of performing new transmission or retransmission further includes maintaining a buffer corresponding to the transport block that has received the NACK response and flushing a buffer corresponding to the transport block that has received the ACK response.

8. The method of claim 5, wherein, if the ACK/NACK responses are all NACK responses and the second new data indicator has the same value that of the first new data indicator, the step of performing new transmission or retransmission further includes maintaining buffers corresponding to the respective transport blocks.

9. A method for performing retransmission at a user equipment of a MIMO wireless communication system, the method comprising:

transmitting a first transport block to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator;

receiving ACK/NACK (Acknowledgement/Negative-ACK) response corresponding to the first transport block and uplink grant information, which includes a second new data indicator, from the base station; and

performing new transmission for a second transport block and new transmission or retransmission for the first transport block in accordance with the ACK/NACK response and the second new data indicator, if transport rank is increased,

wherein the second new data indicator has a value different from that of the first new data indicator.

10. The method of claim 9, wherein, if the ACK/NACK response is ACK response, the step of performing new transmission or retransmission further includes flushing a buffer corresponding to the first transport block and a buffer corresponding to the second transport block.

11. The method of claim 9, wherein, if the ACK/NACK response is NACK response, the step of performing new transmission or retransmission further includes maintaining a buffer corresponding to the first transport block and flushing a buffer corresponding to the second transport block.

12. A user equipment comprising:

a processor; and

a radio frequency (RF) module supporting MIMO antennas and transmitting and receiving a radio signal to and from the outside under the control of the processor,

wherein the processor transmits multiple transport blocks to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator, receives ACK/NACK (Acknowledgement/Negative-ACK) responses corresponding to the respective transport blocks and uplink grant information, which includes a second new data indicator, from the base station, and

performs new transmission or retransmission for the multiple transport blocks in one transport block unit for a transmission unit time in accordance with the ACK/NACK responses and the second new data indicator, if transport rank is reduced to 1.

13. The user equipment of claim 12, wherein, if the ACK/NACK responses are all ACK responses and the second new data indicator has a value different from that of the first new data indicator, the processor flushes a buffer corresponding to one of the multiple transport blocks, which is intended for new transmission.

14. The user equipment of claim 12, wherein, if the ACK/NACK responses includes at least one ACK response and at least one NACK response and the second new data indicator has the same value as that of the first new data indicator, the processor maintains a buffer corresponding to the transport block that has received the NACK response.

15. The user equipment of claim 12, wherein, if the ACK/NACK responses are all NACK responses and the second new data indicator has the same value that of the first new data indicator, the processor maintains buffers corresponding to the respective transport blocks.

16. A user equipment comprising:

a processor; and

a radio frequency (RF) module supporting MIMO antennas and transmitting and receiving a radio signal to and from the outside under the control of the processor,

wherein the processor transmits multiple transport blocks to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator, receives ACK/NACK (Acknowledgement/Negative-ACK) responses corresponding to the respective transport blocks and uplink grant information, which includes a second new data indicator, from the base station, and

performs new transmission or retransmission for the multiple transport blocks in one transport block unit for a transmission unit time in accordance with the ACK/NACK responses and the second new data indicator, if transport rank is maintained.

17. The user equipment of claim 16, wherein, if the ACK/NACK responses are all ACK responses and the second new data indicator has a value different from that of the first new data indicator, the processor flushes buffers corresponding to the multiple transport blocks.

18. The user equipment of claim 16, wherein, if the ACK/NACK responses includes at least one ACK response and at least one NACK response and the second new data indicator has the same value as that of the first new data indicator, the processor maintains a buffer corresponding to the transport block that has received the NACK response and flushes a buffer corresponding to the transport block that has received the ACK response.

19. The user equipment of claim 16, wherein, if the ACK/NACK responses are all NACK responses and the second new data indicator has the same value that of the first new data indicator, the processor maintains buffers corresponding to the respective transport blocks.

20. A user equipment comprising:

a processor; and

a radio frequency (RF) module supporting MIMO antennas and transmitting and receiving a radio signal to and from the outside under the control of the processor,

wherein the processor transmits a first transport block to a base station for a transmission unit time in accordance with uplink grant information, which includes a first new data indicator, receives ACK/NACK (Acknowledgement/Negative-ACK) response corresponding to the first transport block and uplink grant information, which includes a second new data indicator, from the base station, and performs new transmission for a second transport block and new transmission or retransmission for the first transport block in accordance with the ACK/NACK response and the second new data indicator, if transport rank is increased, and

the second new data indicator has a value different from that of the first new data indicator.

21. The user equipment of claim 20, wherein, if the ACK/NACK response is ACK response, the processor flushes a buffer corresponding to the first transport block and a buffer corresponding to the second transport block.

22. The user equipment of claim 20, wherein, if the ACK/NACK response is NACK response, the processor maintains a buffer corresponding to the first transport block and flushes a buffer corresponding to the second transport block.