Method and device for a hybrid automatic repeat request in a multi-carrier system

摘要

A method of performing hybrid automatic repeat request (HARQ) in a carrier aggregation system is provided. The method includes: monitoring a downlink (DL) grant for initial DL data transmission in a first DL component carrier (CC); receiving initial DL data through a second DL CC indicated by the DL grant; decoding the initial DL data; transmitting a not-acknowledgment (NACK) signal when decoding of the initial DL data fails; monitoring a DL grant for retransmission of the DL data in the first DL CC; and receiving DL data retransmitted through the second DL CC, wherein the second DL CC is any one of a plurality of DL CCs having a predetermined link relation with the first DL CC, and the DL grant for the initial transmission includes a carrier indication field indicating the second DL CC and resource allocation information for the initially transmitted DL data.

主权项

1. A method of performing hybrid automatic repeat request (HARQ) in a carrier aggregation system, the method performed by a user equipment (UE) and comprising:
receiving a first downlink (DL) grant for initial DL data transmission in a first DL component carrier (CC), the first DL grant including a carrier indication field (CIF) indicating a second DL CC and resource allocation information for the initial DL data transmission; receiving initial DL data through the second DL CC indicated by the CIF in the first DL grant; decoding the initial DL data; transmitting a negative acknowledgement (NACK) signal when the decoding of the initial DL data fails; receiving a second DL grant for retransmission of the DL data in the first DL CC; determining in which of the first DL CC and the second DL CC the retransmitted DL data is to be received based on the received second DL grant, wherein the retransmitted DL data is determined to be received in the second DL CC instead of the first DL CC if a CIF in the second DL grant does not indicate the second DL CC, wherein the CIF in the second DL grant is transformed to allow the UE to detect an error of resource allocation information for the retransmitted DL data in the second DL grant, rather than the CIF in the second DL grant indicating the second DI CC; and receiving the retransmitted DL data in the second DL CC.