Digital television system

A VSB transmitter for transmitting a terrestrial broadcasting signal including main ATSC data and additional data, the VSB transmitter comprising:

• a multiplexer for multiplexing the main ATSC data and the additional data;
• a first coder for coding a first data bit of the multiplexed data and outputting the coded first data bit if it belongs to the main ATSC data, the first coder directly outputting the first data bit without coding if it belongs to the additional data;
• a second coder for coding a second data bit;
• a VSB mapper for mapping the coded or uncoded first data bit outputted from the first coder and the coded second data bit into a corresponding signal;
• and
• a VSB format converter for formatting the signal ouputted from the VSB mapper and transmitting the formatted signal to one or more VSB receivers.

A VSB receiver for receiving and decoding an input signal including main ATSC data and additional data transmitted from a VSB transmitter, the VSB receiver comprising:

• a signal receiver for receiving the input signal including main ATSC data and additional data transmitted from the VSB transmitter;
• a decoder for decoding the main ATSC data and the additional data;
• and
• a signal processor for performing a hard decision only on the main ATSC data.