US Patent 8151157 Method of encoding/decoding using low density check code matrix

A method of encoding data using a parity check matrix, a method of decoding encoded data, and a data retransmission method using the same are disclosed. A method of encoding data by LDPC code using a parity check matrix includes variably selecting a specific sub-matrix from a parity check matrix in accordance with a coding rate to be used for encoding, the parity check matrix including at least two sub-matrixes, and encoding an input data stream by using the selected sub-matrix.