Patent ID: 7804909

Claim:
A digital television (DTV) transmitter for coding main and enhanced data for transmission, the DTV transmitter comprising: a pre-coder for pre-coding the enhanced data by coding the enhanced data for forward error correction (FEC); a data formatter for generating enhanced data packets based on the pre-coded enhanced data; a first multiplexer for multiplexing main data packets including the main data with the enhanced data packets; a data randomizer for randomizing data output from the first multiplexer; a Reed-Solomon (RS) encoder for RS-coding the randomized data by adding first parity data; a data interleaver for interleaving the RS-coded data to output a data structure comprising a plurality of data segments, each of the data segments comprising 207 bytes, wherein a known data sequence is included in N bytes of a K-th data segment of the data structure and in M bytes of a (K+1)-th data segment of the data structure, wherein a plurality of MPEG header bytes are included in L bytes in a J-th data segment of the data structure, wherein L is less than N or M, and wherein N is not equal to M; and a trellis encoder for trellis-encoding the interleaved data, the trellis encoder being initialized when the known data sequence is inputted to the trellis encoder.