Patent ID: 7620118

Claim:
A digital television (DTV) transmitter for coding enhanced data for transmission, the DTV transmitter comprising: a data formatter for generating an enhanced data packet including the enhanced data and a known data sequence; a data randomizer for randomizing the enhanced data packet; a Reed-Solomon (RS) encoder for RS-coding the randomized data packet by adding first parity data; a data interleaver for interleaving the RS-coded data packet; a trellis encoding unit for trellis-encoding the interleaved data packet; and a multiplexer for multiplexing the trellis-encoded data packet with field and segment synchronization signals, wherein the trellis encoding unit comprises: a trellis-coded modulation (TCM) encoder for generating a first output bit by trellis-encoding a first input bit and generating a second output bit by bypassing the first input bit; and a pre-coder for generating a third output bit by pre-coding a second input bit, wherein memories included in the TCM encoder and the pre-coder are initialized when the known data sequence is input to the trellis encoding unit.