Patent ID: 8458752

Claim:
A method of transmitting a broadcast signal in a transmitter, the method comprising: encoding mobile data for additional forward error correction (FEC); forming data groups of the encoded mobile data, each formed data group including the encoded mobile data, signaling information and a plurality of known data sequences, wherein at least two of the plurality of known data sequences have different lengths, and wherein placeholders for the main data, an MPEG-2 header and non-systematic Reed-Solomon (RS) parity data are inserted in each formed data group; de-interleaving data in the formed data groups; removing the placeholder for the main data and non-systematic RS parity data; replacing the placeholder for the MPEG-2 header with MPEG-2 headers; outputting mobile data packets including the MPEG-2 headers and data in the data groups; multiplexing main data packets including main data with the output mobile data packets; performing systematic RS encoding on the main data in the multiplexed data packets; performing non-systematic RS encoding on the mobile data in the multiplexed data packets; and transmitting the broadcast signal including the systematic RS encoded main data and the non-systematic RS encoded mobile data.