Patent ID: 8327210

Claim:
A method for providing a multicast service by a base station (BS) in a wireless communication system, the method comprising: transmitting an N th data traffic corresponding to a multicast service to a plurality of mobile stations (MSs) through a multicast channel in an F th frame; determining whether a Negative Acknowledgement (NACK) message indicating a failure to receive the N th data traffic is received from at least one mobile station (MS) in an (F+1) th frame; and in response to receiving the NACK message, retransmitting the N th data traffic to the at least one MS through another channel different from the multicast channel in an (F+2) th frame, wherein a frame where the N th data traffic is retransmitted, and a position where the retransmitted N th data traffic is situated in a data burst region of a frame are indicated in the F th frame.