Patent ID: 8189546

Claim:
A data transmission method for an MBS (Multicast & Broadcast Service) in a broadband wireless access system, the method comprising the steps of: constructing first and second Wibro frames for non-simultaneous transmission, each having a structure comprising a downlink portion in which data is transmitted from a radio access station (RAS) to a plurality of mobile stations, temporally followed by an uplink portion in which data is transmitted from at least one mobile station to the RAS and downlink data is not transmitted by the RAS, wherein, the downlink portion of the first Wibro frame contains at least broadcast data containing packets of a broadcast channel; and the downlink portion of the second Wibro frame contains an FEC (Forward Error Correction) zone, the FEC zone containing an FEC packet corresponding to a data packet in the broadcast data of the first frame, for performing a packet-based FEC process on the corresponding data packet of the first frame; and transmitting, by the RAS, the first and second Wibro frames to the plurality of mobile stations.