Patent ID: 8750219

Claim:
A base station apparatus for receiving an uplink shared channel from a user apparatus and informing the user apparatus whether the user apparatus has to retransmit the uplink shared channel, comprising: a transmit power control unit configured to determine transmit power for a HARQ indicator channel for indicating a positive response or a negative response to the uplink shared channel; and a transmitting unit configured to transmit a transmission signal to the user apparatus, the transmission signal including the HARQ indicator channel at the transmit power determined by the transmit power control unit, wherein the transmit power control unit determines the transmit power for the HARQ indicator channel based on reference transmit power, reference radio quality information, downlink radio quality information and an offset, and different offsets are set depending on whether the transmission signal includes a control channel for allowing the uplink shared channel to be transmitted and whether the transmission signal includes the HARQ indicator channel indicative of the positive response.