Method for effectively transmitting control signal in wireless communication system

1. A method of performing Hybrid Automatic Repeat request (HARQ) performed by a user equipment (UE) in a wireless communication system, the method comprising:

receiving a bundling indicator which indicates the number of bundled downlink subframes, each subframe of the bundled downlink subframes being used to transmit one or plural codewords;

determining whether at least one bundled downlink subframe is missed by comparing the bundling indicator with the number of detected bundled downlink subframes;

generating a representative ACK/NACK signal when no bundled downlink subframe is missed, wherein the representative ACK/NACK signal is an ACK signal if all codewords in the detected bundled downlink subframes are successfully received; and

transmitting the representative ACK/NACK signal on an uplink channel,

wherein the bundling indicator is received on a downlink channel, the resource for the uplink channel is associated with the downlink channel for the nearest bundled downlink subframe to the uplink subframe

and wherein the uplink channel is Physical Uplink Control Channel (PUCCH).

2. The method of claim 1 , wherein the representative ACK/NACK signal is not transmitted if at least one bundled downlink subframe is missed.

3. The method of claim 1 , wherein an uplink resource for the uplink channel carrying the representative ACK/NACK signal is associated with the last detected bundled downlink subframe.

4. The method of claim 1 , further comprising:

generating the representative ACK/NACK signal as a NACK signal if at least one bundled downlink subframe is missed.

5. The method of claim 1 , wherein the bundling indicator is included in uplink scheduling information.