Patent ID: 7904785

Claim:
A digital television (DTV) transmitting system for processing digital broadcast data, the DTV transmitting system comprising: Reed-Solomon (RS) frame encoder generating an RS frame by adding RS parity data to bottom ends of columns of an RS frame payload and adding Cyclic Redundancy Check (CRC) checksum data to right ends of rows of the RS frame payload, the RS frame payload including enhanced data; a block processor for encoding a first portion of the enhanced data with a first coding rate and encoding a second portion of the enhanced data with a second coding rate, wherein the first coding rate is different from the second coding rate; a group formatter for mapping the encoded first portion of the enhanced data into a first region of at least one data group, mapping the encoded second portion of the enhanced data into a second region of the at least one data group, and adding known data sequences and signaling information to the first region of each data group, wherein the second region includes main data; a trellis encoder for trellis encoding the at least one data group; and a transmitting unit for modulating the trellis-encoded at least one data group and transmitting the modulated at least one data group.