Patent ID: 7131049

Claim:
A method for generating a retransmission puncturing pattern matrix in order to transmit a packet unit including a stream of symbols and another stream of symbols according to a first modulation type and a second modulation type in response to a retransmission request from a receiver, in a mobile communication system puncturing coded bits from an encoder according to a first puncturing pattern matrix given based on the first modulation type, and transmitting a packet unit including a stream of symbols obtained by symbol mapping the punctured coded bits by the first modulation type, from a transmitter to the receiver, the method comprising the steps of: calculating a number of bits per a puncturing pattern matrix, to be increased or decreased, by multiplying a difference B N −B 0 between a number B N of coded bits that can be mapped to one symbol by the second modulation type and a number B 0 of coded bits that can be mapped to one symbol by the first modulation type, by a number B of symbols mapped to bits that are not punctured according to the first puncturing pattern matrix given based on the first modulation type; generating a second puncturing pattern matrix based on the number of bits per the puncturing pattern matrix; and generating the retransmission puncturing pattern matrix by combining the first puncturing pattern matrix with the second puncturing pattern matrix.