Method and apparatus for transmission of reverse-link control-channel acknowledgement channel for forward-link shared control channel in mobile communication systems using orthogonal frequency division multiplexing access

An apparatus and a method for transmitting an R-scchACKCH(Reverse-link scchACKCH) about a F-SCCH(Forward-link Shared Control Channel) in a mobile communication system of OFDM are provided to reduce the number of times of backward transmission of R-scchACKCH by responding a modulation accomplishment result of a control channel through R-scchACKCH according to predetermined transmission time point. A base station transmits a first sub packet of F-SCCH and a first F-DCH packet to a mobile terminal(604). The base station transmits a second sub packet again because the terminal does not respond nothing(606). If the mobile terminal modulates the data successfully after receiving the second sub packet, the mobile terminal transmits ACK to the R-scchACKCH(608). The base station which receives the ACK through the R-scchACKCh transmits a third sub packet(610). If the mobile terminal succeeds the modulation for the third sub packet, the mobile terminal transmits the ACK to the base station through the R-ACKCH(612). The base station which receives the ACK through the P-ACKCH recognizes that the mobile terminal has received the first packet successfully, and transmits the F-SCCH and the F-DCH to the mobile terminal, so as to report a new packet and control information about the new packet.