Patent ID: 7933356

Claim:
A digital television (DTV) transmitter comprising: a first encoder for generating a Reed-Solomon (RS) frame by adding RS parity data and cyclic redundancy check (CRC) data to enhanced data; a second encoder for encoding the enhanced data in the RS frame with an encoding rate of 1/H, wherein H≧2; a symbol interleaver for interleaving symbols corresponding to the encoded enhanced data, wherein the symbol interleaver interleaves the symbols using the following steps: calculating L, wherein L=2 m , and wherein m is an integer, listing all permuted positions P′(i) in ascending order of i according to the following equation: P′(i)={89*i*(i+1)/2} mod L, wherein i is a natural number from 0 to L-1, discarding all P′(i) that are P′(i)≧B, wherein B is a block length of symbols being input to the symbol interleaver, and condensing the list by, starting with a lowest i, shifting P(i) entries to the left to fill empty locations created by the discarding step; a group formatter for mapping enhanced data corresponding to the interleaved symbols into a data group and adding known data sequences and signaling information into the data group; a trellis encoder for trellis encoding the data group; and a modulator for modulating a broadcast signal including the trellis-encoded data group.