Patent ID: 7940854

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 for forward error correction (FEC); a data formatter for generating enhanced data packets including the pre-coded enhanced data, the enhanced data packets including a plurality of known data sequences; a first multiplexer for multiplexing the enhanced data packets with main data packets including the main data; an RS encoder for RS-coding the multiplexed main and enhanced data packets, the RS encoder adding systematic RS parity data to the main data packets and adding non-systematic RS parity data to the enhanced data packets; a data interleaver for interleaving the RS-coded main and enhanced data packets; a trellis encoder for trellis-encoding data in the interleaved main and enhanced data packets, wherein the trellis encoder includes memories initialized by initialization data at a start of each of the plurality of known data sequences; a non-systematic RS encoder for generating new parity data based on the initialization data and outputting the generated new parity data; and a second multiplexer for selecting the data in the interleaved main and enhanced data packets output from the data interleaver and the generated new parity data output from the non-systematic RS encoder and providing the selected data to the trellis encoder.