Apparatus and method for increasing service coverage of broadcast channel in wireless mobile communication system

An apparatus and a method for enlarging the coverage of a broadcast channel in a mobile communication system are provided to enable a mobile station in a band channel state to successfully receive a long management message by increasing the service coverage of a broadcast control channel through a HARQ(Hybrid Automatic Repeat Request) technique. A mobile station receives a long management message which contains a long management message payload and a retransmission indication header, and attempts decoding with the long management message payload only(501). Then the mobile station checks whether payload decoding has been successfully completed(503). If not, the mobile station decodes the retransmission indication header and judges whether HARQ recombination is possible(505). In case HARQ recombination is possible, the mobile station extracts a payload equivalent to the same management message type as the received long management message from a data buffer and recombines the extracted payload with the long management message payload of the received long management message(509). Then the mobile station attempts decoding for the recombined payload again(511), and checks whether payload decoding has been successfully completed(513).