Method and apparatus for transmitting and receiving downlink control information in a mobile communication system supporting uplink packet data

A method of transmitting control information for uplink packet data reception for a User Equipment (UE) including a plurality of hybrid automatic repeat request (HARQ) processes, in a Node B of a mobile communication system, comprising the steps of:

• determining an allowed maximum power ratio for a HARQ process of the UE;
• setting a relative grant (RG) associated with the HARQ process to hold so that the UE sets the allowed maximum power ratio in the HARQ process to an allowed maximum power ratio of an immediately previous transmission time interval (TTI) of the HARQ process;
• and
• transmitting the RG associated with the HARQ process to the UE by the Node B;
• wherein if the RG is set to hold, the transmission step comprises the step of transmitting the RG to the UE in a discontinuous transmission (DTX) mode.

An apparatus for transmitting uplink packet data in a User Equipment (UE) of a mobile communication system, the UE including a plurality of hybrid automatic repeat request (HARQ) processes, comprising:

• a receiver for receiving a relative grant (RG) associated with a HARQ process from a Node B;
• a controller for setting an allowed maximum power ratio in the HARQ process to an allowed maximum power ratio in an immediately previous transmission time interval (TTI) of the HARQ process, if the RG indicates hold;
• and
• a transmitter for transmitting an uplink packet data within the set allowed maximum power ratio in the HARQ process to the Node B;
• wherein if the RG indicates hold, the RG is received from the Node B in a discontinuous transmission (DTX) mode.

An apparatus for transmitting control information for uplink packet data reception for a User Equipment (UE) including a plurality of hybrid automatic repeat request (HARQ) processes, in a Node B of a mobile communication system, comprising:

• a controller for determining an allowed maximum data rate for a HARQ process of the UE and setting an RG associated with the HARQ process to hold, so that the UE sets the allowed maximum power ratio of the HARQ process to an allowed maximum power ratio of an immediately previous transmission time interval (TTI) of the HARQ process;
• and
• a transmitter for transmitting the RG to the UE;
• wherein if the RG is set to hold, the transmitter transmits a discontinuous transmission (DTX) signal to the UE.