Method for processing NDI in random access procedure and a method for transmitting and receiving a signal using the same

• US 7,961,680 B2
• Filed: 07/02/2009
• Issued: 06/14/2011
• Est. Priority Date: 07/03/2008
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Park, Sung Jun, Lee, Young Dae, Yi, Seung June, Chun, Sung Duck
• Primary Examiner(s): Trost, IV; William
• Assistant Examiner(s): Nguyen; Toan D
• Application Number:
  US12/496,721
• Publication Number:
  US 20100002630A1
• Time in Patent Office: 712 Days
• Field of Search: 370/229, 370/328, 370/329, 370/335, 370/338, 455/436, 455/437
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1822 involving configuration of automatic repeat request [ARQ] with parallel processes
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access

Abstract

A method for a user equipment (UE) to transmit an uplink signal, and which includes receiving a first downlink control channel identified by a temporary cell identifier (Temporary C-RNTI) from a base station, the first downlink control channel including a first uplink grant signal having a new data indicator (NDI) with a first value; receiving a second downlink control channel identified by a cell identifier (C-RNTI) from the base station, the second downlink control channel including a second uplink grant signal having the NDI with a second value; and determining if the NDI with the second value has been toggled compared to the NDI previously received from the base station. Further, the UE ignores the NDI with the first value received through the first downlink control channel identified by the temporary cell identifier (Temporary C-RNTI). The method also includes transmitting the uplink signal based on the determining.

Claims

1. A method for a user equipment (UE) to transmit an uplink signal, the method comprising:

receiving a first downlink control channel identified by a temporary cell identifier (Temporary C-RNTI) from a base station, the first downlink control channel comprising a first uplink grant signal having a new data indicator (NDI) with a first value;

receiving a second downlink control channel identified by a cell identifier (C-RNTI) from the base station, the second downlink control channel comprising a second uplink grant signal having the NDI with a second value;

determining if the NDI with the second value has been toggled compared to the NDI previously received from the base station, wherein the UE ignores the NDI with the first value received through the first downlink control channel identified by the temporary cell identifier (Temporary C-RNTI); and

transmitting the uplink signal based on the determining.

2. The method of claim 1, wherein the NDI previously received from the base station comprise the NDI received through a third downlink control channel identified by the cell identifier (C-RNTI), the third downlink control channel received before receiving the second downlink control channel.

3. The method of claim 1, wherein the second value of the NDI is associated with a specific HARQ process, and

wherein the determining comprises determining if the second value of the NDI has been toggled compared to the value of the NDI in a previous transmission of the specific HARQ process.

4. The method of claim 3, wherein transmitting the uplink signal comprises transmitting new data by the specific HARQ process, when the second value of the NDI has been toggled compared to the value in the previous transmission of the specific HARQ process.

5. The method of claim 3, wherein transmitting the uplink signal comprises transmitting retransmission data by the specific HARQ process, when the second value of the NDI has not been toggled compared to the value in the previous transmission of the specific HARQ process.

6. The method of claim 1, wherein the first uplink grant signal is received during a random access procedure, and

wherein the second uplink grant signal is received after the random access procedure.

7. The method of claim 6, wherein the first uplink grant signal is received at a timing associated to a first HARQ process, the random access procedure is successfully completed by a random access using a second HARQ process, and the second uplink grant signal is received at a timing associated to the first HARQ process, and

wherein when determining if the NDI has been toggled compared to the value in the previous transmission of the first HARQ process, the UE ignores the NDI received at the timing associated to the first HARQ process during the random access procedure.

8. A user equipment comprising:

a physical layer module including a receiving module and a transmitting module, the receiving module for receiving a downlink control channel and a downlink shared channel, the downlink control channel including a new data indicator (NDI) toggled if a base station indicates new transmission; and

a MAC layer module including a plurality of HARQ process modules, a plurality of buffers respectively corresponding to the plurality of HARQ process modules, and a single HARQ entity, the HARQ entity controlling the plurality of HARQ process modules to allow a specific one of the HARQ process modules to process the downlink control channel and the downlink shared channel received by the receiving module and an uplink shared channel transmitted from the transmitting module,

wherein the HARQ entity or the specific HARQ process module compares an NDI bit value previously stored in a specific buffer corresponding to the specific HARQ process module with an NDI value received in correspondence with the specific HARQ process module to determine whether to perform retransmission depending on whether the NDI bit value has been toggled, and ignores the NDI received using a temporary cell identifier stored in the specific buffer when the HARQ entity or the specific HARQ process module determines whether the NDI bit value has been toggled.