Patent ID: 7733817

Claim:
A receiving system, comprising: a signal receiving unit configured to receive a broadcast signal, the broadcast signal comprising a data group, wherein the data group comprises a plurality of known data sequences, which is known by transmitting and receiving sides in advance and differs from each other in length, and mobile service data between the plurality of known data sequences; a known data detector configured to detect the plurality of known data sequences from the broadcast signal; an equalizer configured to compensate for channel distortion of the mobile service data within the data group using a channel impulse response (CIR) estimated based on the plurality of detected known data sequences; a block decoder configured to perform decoding by a block unit on the channel distortion compensated mobile service data; and an error correction unit configured to estimate the number of errors by performing Cyclic Redundancy Check (CRC) decoding on each row of an Reed Solomon (RS) frame including the block-decoded mobile service data, and generate a reliability map representing reliability information of each mobile service data byte within the RS frame, wherein the error correction unit sets an erasure point in a corresponding mobile service data byte based upon the reliability information of each mobile service data byte of a corresponding column and position of errors if the number of errors estimated from the RS frame is greater than the number of RS parity data added to the column of the RS frame, and wherein the error correction unit performs any one of general RS decoding and RS erasure decoding on the column based upon the number of erasure points in the column.