US Patent 8219869 Method of retransmitting data in a mobile communication system

A communication method according to an automatic repeat request scheme in a mobile communication system includes transmitting a retransmission packet per certain time period (periodically) in response to NACK of a first user equipment related to a first packet transmitted within a frame group consisting of a plurality of successive frames, and transmitting a retransmission packet non-periodically in response to NACK of a second user equipment related to a second packet transmitted within the frame group.