Method and apparatus for performing HARQ in multiple carrier system

• US 8,630,248 B2
• Filed: 07/16/2010
• Issued: 01/14/2014
• Est. Priority Date: 07/16/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Seo, Dong Youn, Yang, Suck Chel, Ahn, Joon Kui
• Primary Examiner(s): Sam, Phirin
• Application Number:
  US13/384,030
• Publication Number:
  US 20120113946A1
• Time in Patent Office: 1,278 Days
• Field of Search: None
• US Class Current: 370/329
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1861 Physical mapping arrangements for ACK signaling see also H04L5/0053
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0055 Physical resource allocation for ACK/NACK for physical mapping arrangements in ARQ protocols H04L1/1861
• CPC Class Codes: H04L 5/0082 at predetermined intervals
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated

Abstract

A method and apparatus for performing hybrid automatic repeat request (HARQ) in a multiple carrier system are provided. A user equipment performs an HARQ process in a source component carrier. When the user equipment receives a management message regarding a transfer from the source component carrier to a target component carrier, the user equipment subsequently performs the HARQ process in the target component carrier.

Claims

1. A method of performing hybrid automatic repeat request (HARQ) by a user equipment in a multiple carrier system, the method comprising:

receiving a first downlink grant on a downlink control channel through a first component carrier, the first downlink grant including a first HARQ process index (HID) indicating an HARQ process index and a first new data indicator (NDI) indicating a new transmission or a retransmission;

receiving a downlink transfer block on the downlink data channel indicated by a resource allocation in the first downlink grant through the first component carrier;

transmitting a NACK signal for the downlink transport block;

receiving a second downlink grant on the downlink control channel through a second component carrier different from the first component carrier, the second downlink grant including a second HID indicating same HARQ process as the first HID and a second NDI indicating a retransmission of the downlink transfer block which has been transmitted through the first component carrier; and

receiving the retransmission of the downlink transfer block through the second component carrier.

2. The method of claim 1, wherein if the second NDI is set to 1, the retransmission is indicated.

3. The method of claim 1, wherein a value of the first HID is same as a value of the second HID.

4. The method of claim 1, wherein the downlink transfer block is used for a semi-persistent scheduling (SPS).

5. The method of claim 1, further comprising:

receiving a management message regarding a transfer from the first component carrier to the second component carrier.

6. A user equipment comprising:

a radio frequency (RF) unit for transmitting and receiving a radio signal; and

a processor, coupled to the RF unit, for performing hybrid automatic repeat request (HARQ), and configured to;

receive a first downlink grant on a downlink control channel through a first component carrier, the first downlink grant including a first HARQ process index (HID) indicating an HARQ process index and a first new data indicator (NDI) indicating a new transmission or a retransmission;

receive a downlink transfer block on the downlink data channel indicated by a resource allocation in the first downlink grant through the first component carrier;

transmit a NACK signal for the downlink transport block;

receive a second downlink grant on the downlink control channel through a second component carrier different from the first component carrier, the second downlink grant including a second HID indicating same HARQ process as the first HID and a second NDI indicating a retransmission of the downlink transfer block which has been transmitted through the first component carrier; and

receive the retransmission of the downlink transfer block through the second component carrier.

7. The user equipment of claim 6, wherein if the second NDI is set to 1, the retransmission is indicated.

8. The user equipment of claim 6, wherein a value of the first HID is same as a value of the second HID.

9. The user equipment of claim 6, wherein the downlink transfer block is used for a semi-persistent scheduling (SPS).

10. The user equipment of claim 6, wherein the processor is further configured to receive a management message regarding a transfer from the first component carrier to the second component carrier.