Patent ID: 7738908

Claim:
A base station apparatus for transmitting data in order to determine transmit power of an uplink frame in a mobile communication system, the base station apparatus comprising: an error detector for determining if an error has occurred in an uplink frame received from a subscriber station; an upper layer processor for receiving information related to whether or not the error has occurred in the uplink frame from the error detector and generating an ACK/NACK message of an upper layer according to the information for transmitting data in order to determine transmit power of the uplink frame transmitted from the subscriber station to a base station; and a transmitter for performing a transmission processing for the ACK/NACK message generated by the upper layer processor, wherein the ACK/NACK message is used for determining the transmit power of the uplink frame by the subscriber station, and wherein the transmit power of the uplink frame is adjusted by Offset perAT =Offset perAT +UP_STEP, if NACK is received, where Offset perAT represents a compensation value to be added to a previous transmit power for each subscriber station, and UP_STEP represents an increase of the Offset perAT .