DTV transmitting system and receiving system and method of processing broadcast signal

Abstract

A DTV transmitting system includes a pre-processor, a block processor, and a trellis encoder. The pre-processor pre-processes enhanced data by expanding the enhanced data at an expansion rate of 1/H. The block processor includes a first converter, a symbol encoder, a symbol interleaver, and a second converter. The first converter converts the expanded data into symbols. The symbol encoder encodes each valid enhanced data bit in the symbol at an effective coding rate of 1/H. The symbol interleaver interleaves the encoded symbols, and the second converter converts the interleaved symbols into enhanced data bytes. The trellis encoder trellis-encodes the enhanced data outputted from the block processor.

What is claimed: 
     
       1. A digital television (DTV) transmitter for processing digital broadcast data, the DTV transmitter comprising:
 a randomizer configured to randomize enhanced data;   a first encoder configured to generate a Reed Solomon (RS) frame by adding RS parity data and cyclic redundancy check (CRC) data to the randomized enhanced data;   a second encoder configured to encode the enhanced data in the RS frame with an encoding rate of 1/H, wherein H≧2;   a symbol interleaver configured to interleave symbols corresponding to the encoded enhanced data, wherein the symbol interleaver interleaves the symbols by:
 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 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; 
   a group formatter configured to map enhanced data corresponding to the interleaved symbols into data groups, wherein at least one of the data groups further includes known data sequences, signaling information and moving picture experts group (MPEG) header place holders;   a deinterleaver configured to deinterleave data of the data groups;   a packet formatter configured to replace the MPEG header place holders in the deinterleaved data with MPEG header data and output enhanced data packets;   an interleaver configured to interleave data in the enhanced data packets; and   a modulator configured to modulate a broadcast signal having the interleaved data.   
     
     
       2. The DTV transmitter of  claim 1 , wherein the deinterleaver performs a reverse operation of the interleaver. 
     
     
       3. The DTV transmitter of  claim 1 , wherein the at least one of the data groups includes first, second and third regions, wherein the first region includes the known data sequences. 
     
     
       4. The DTV transmitter of  claim 1 , further comprising:
 a trellis encoder configured to trellis encode the interleaved data.   
     
     
       5. The DTV transmitter of  claim 4 , wherein the at least one of the data groups includes initialization data for initialization of memory in the trellis encoder, wherein the initialization data is located in front of the known data sequences. 
     
     
       6. A method for processing digital broadcast data in a digital television (DTV) transmitter, the method comprising:
 randomizing enhanced data; 
 generating a Reed Solomon (RS) frame by adding RS parity data and cyclic redundancy check (CRC) data to the randomized enhanced data; 
 encoding the enhanced data in the RS frame with an encoding rate of 1/H, wherein H≧2 H is greater than or equal to 2; 
 interleaving symbols corresponding to the encoded enhanced data, wherein the symbol interleaver interleaves the symbols by:
 calculating L, wherein L=2 m  [L=2m]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 greater than or equal to B, wherein B is a block length of symbols input to the symbol interleaver, and 
 condensing the list by, starting with a lowest i, shifting P(i) entries to the left starting with a lowest i to fill empty locations created by the discarding; 
 
 mapping enhanced data corresponding to the interleaved symbols into data groups, wherein at least one of the data groups further includes known data sequences, signaling information and moving picture experts group (MPEG) header place holders; 
 deinterleaving data of the data groups; 
 replacing the MPEG header place holders in the deinterleaved data with MPEG header data and outputting enhanced data packets; 
 interleaving data in the enhanced data packets; and 
 modulating a broadcast signal having the interleaved data. 
 
     
     
       7. The method of  claim 6 , wherein the deinterleaving the data of the data groups is a reverse operation of the interleaving the symbols. 
     
     
       8. The method of  claim 6 , wherein the at least one of the data groups includes first, second and third regions, wherein the first region includes the known data sequences. 
     
     
       9. The method of  claim 6 , further comprising:
 trellis encoding the interleaved data. 
 
     
     
       10. The method of  claim 8 , wherein the at least one of the data groups includes initialization data for initialization of memory in a trellis encoder, wherein the initialization data is located in front of the known data sequences. 
     
     
       11. The method of claim 6, further comprising:
 independently block-encoding the enhanced data packets for forward error correction (FEC); and   independently interleaving the block-encoded enhanced data packets.