Enhanced VSB Viterbi decoder

Abstract

An enhanced VSB receiver includes a tuner which tunes an RF signal and converts it into an IF signal, an IF mixer which converts the IF signal into a baseband signal, and a demodulator which demodulates the baseband signal into a VSB signal. The enhanced VSB receiver further includes a map recovery unit which recovers VSB map information of the VSB signal, an enhanced equalizer for compensating channel distortion of the VSB signal and outputting an equalized symbol, and an enhanced Viterbi decoder for estimating whether polarity inversion occurred during a symbol period of the equalized symbol and Viterbi-decoding the equalized symbol based on the polarity estimation.

What is claimed is: 
     
       1. A method for processing a digital television (DTV) broadcast signal in a broadcasting receiver, the method comprising:
 receiving, by a tuner, the DTV broadcast signal including enhanced data;   equalizing the received DTV broadcast signal by compensating channel distortion of the received DTV broadcast signal;   decoding signaling information from the equalized DTV broadcast signal, wherein the signaling information includes information indicating whether the enhanced data are coded at a ½ code rate or at a ¼ code rate;   decoding, by a decoder, the enhanced data included in the equalized DTV broadcast signal; and   derandomizing, by a derandomizer, the decoded enhanced data,   wherein the enhanced data in the received DTV broadcast signal are generated in a broadcast transmitter by:   randomizing original enhanced data,   first Reed Solomon (RS) encoding the randomized original enhanced data,   convolutional encoding the first RS-encoded original enhanced data,   second RS encoding the convolutional encoded original enhanced data,   interleaving the second RS-encoded original enhanced data, and   trellis encoding the interleaved original enhanced data.   
     
     
       2. The method of  claim 1 , wherein the received DTV broadcast signal further includes main data that the convolutional encoding is not performed. 
     
     
       3. The method of  claim 1 , wherein the enhanced data is decoded based on the signaling information. 
     
     
       4. The method of  claim 1 , wherein the received DTV broadcast signal further includes segment synchronization data and field synchronization data. 
     
     
       5. A broadcasting receiver for processing a digital television (DTV) broadcast signal, the broadcasting receiver comprising:
 a tuner for receiving the DTV broadcast signal including enhanced data;   an equalizer for equalizing the received DTV broadcast signal by compensating channel distortion of the received DTV broadcast signal;   an information recovery unit for decoding signaling information from the equalized DTV broadcast signal, wherein the signaling information includes information indicating whether the enhanced data are coded at a ½ code rate or at a ¼ code rate;   a decoder for decoding the enhanced data included in the equalized DTV broadcast signal; and   a derandomizer for derandomizing the decoded enhanced data,   wherein the enhanced data in the received DTV broadcast signal are generated in a broadcast transmitter by:   randomizing original enhanced data,   first Reed Solomon (RS) encoding the randomized original enhanced data,   convolutional encoding the first RS-encoded original enhanced data,   second RS encoding the convolutional encoded original enhanced data,   interleaving the second RS-encoded original enhanced data, and   trellis encoding the interleaved original enhanced data.   
     
     
       6. The broadcasting receiver of  claim 5 , wherein the received DTV broadcast signal further includes main data that the convolutional encoding is not performed. 
     
     
       7. The broadcasting receiver of  claim 5 , wherein the decoder decodes the enhanced data based on the signaling information. 
     
     
       8. The broadcasting receiver of  claim 5 , wherein the received DTV broadcast signal further includes segment synchronization data and field synchronization data. 
     
     
       9. A method for processing a broadcast signal in a broadcasting receiver, the method comprising:
 receiving the broadcast signal including first enhanced data, second enhanced data and signaling information, wherein the first enhanced data are encoded at a first code rate and the second enhanced data are encoded at a second code rate;   demodulating the received broadcast signal;   decoding the signaling information in the demodulated broadcast signal, wherein the decoded signaling information includes information for identifying the first enhanced data and the second enhanced data;   decoding the first enhanced data in the demodulated broadcast signal based on the decoded signaling information; and   decoding the second enhanced data in the demodulated broadcast signal based on the decoded signaling information.   
     
     
       10. The method of claim 9, further comprising:
 derandomizing the decoded first enhanced data and the decoded second enhanced data.   
     
     
       11. The method of claim 9, wherein the broadcast signal further includes main data multiplexed with the first and second enhanced data. 
     
     
       12. The method of claim 11, wherein the decoded signaling information further includes information for identifying the main data. 
     
     
       13. A broadcasting receiver for processing a broadcast signal, the broadcasting receiver comprising:
 a tuner for receiving the broadcast signal including first enhanced data, second enhanced data and signaling information, wherein the first enhanced data are encoded at a first code rate and the second enhanced data are encoded at a second code rate;   a demodulator for demodulating the received broadcast signal;   a signaling decoder for decoding the signaling information in the demodulated broadcast signal, wherein the decoded signaling information includes information for identifying the first enhanced data and the second enhanced data; and   a decoder for decoding the first enhanced data in the demodulated broadcast signal based on the decoded signaling information and decoding the second enhanced data in the demodulated broadcast signal based on the decoded signaling information.   
     
     
       14. The broadcasting receiver of claim 13, further comprising:
 a derandomizer for derandomizing the decoded first enhanced data and the decoded second enhanced data.   
     
     
       15. The broadcasting receiver of claim 13, wherein the broadcast signal further includes main data multiplexed with the first and second enhanced data. 
     
     
       16. The broadcasting receiver of claim 15, wherein the decoded signaling information further includes information for identifying the main data.