Digital broadcast transmitting and receiving system having an improved receiving performance and signal processing method thereof

A stream processing method of a digital broadcast transmitter, comprising the steps of:

• adding known data in a data stream;
• performing interleaving of the data stream;
• and
• performing trellis encoding of the interleaved data stream, including the known data that is known between the transmitter and a receiver, using a trellis encoder having internal memories, and resetting the internal memories before the trellis encoding is performed on the known data,
• wherein the internal memories are reset when the known data is input to the trellis encoder,
• wherein the known data is distinct from a field sync and a segment sync of the data stream and is positioned on a data area, not a sync signal area, in the data stream, and
• wherein one field of the interleaved data stream includes six of the known data.

A digital broadcast system comprising:

• a digital broadcast transmitter to transmit a data stream including a known data;
• and
• a digital broadcast receiver to detect the known data, if the data stream is received, and to process the data stream using the detected known data,
• wherein the digital broadcast transmitter comprises an interleaver to perform interleaving of the data stream and a trellis encoder to perform trellis encoding of the interleaved data stream, including the known data, using internal memories and to reset the internal memories before the trellis encoding is performed on the known data, and a known data processing unit to add the known data in the data stream
• wherein the internal memories are reset when the known data is input to the trellis encoder,
• wherein the known data is distinct from a field sync and a segment sync of the data stream and is positioned on a data area, not a sync signal area, in the data stream, and
• wherein one field of the interleaved data stream includes six of the known data.