Patent ID: 7936837

Claim:
A 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 including the pre-coded enhanced data; a first multiplexer for multiplexing the enhanced data packets with main data packets including the main data; a data randomizer for randomizing the multiplexed enhanced and main data packets; a first RS encoder for RS-coding the randomized data packets, the RS encoder adding first systematic parity data to each main data packet and adding first RS parity data to each enhanced data packet; and a first data interleaver for interleaving the RS-coded main and enhanced data packets, the interleaved enhanced data packets including a plurality of known data sequences, wherein an output of the first interleaver includes a first data group including rows having a length of 207 bytes, an ith row in the first data group having N consecutive MPEG header bytes, and an input of the first interleaver includes a second data group including rows having a length of 207 bytes, an ith row in the second data group having M MPEG header bytes, wherein N>M and N>i.