Digital broadcast transmitter and receiver and method for processing stream thereof

1. A digital broadcast receiver comprising:

a receiver which receives a transport stream transmitted from a digital broadcast transmitter;

an additional data stream detector which determines whether the received transport stream includes an additional data stream with an additional error correction coding; and

a processor which processes the additional data stream if the transport stream includes the additional data stream,

wherein if the transport stream includes the additional data stream, the transport stream includes a training signal which resets memories used for trellis-encoding at a predetermined time, and

wherein the additional data stream detector determines whether the transport stream includes the additional data stream according to whether forward error correction (FEC) coding is performed with respect to a predetermined symbol of the field sync signal.

2. The digital broadcast receiver as claimed in claim 1 , further comprising:

a demodulator which demodulates the received transport stream; and

an equalizer which equalizes the demodulated transport stream,

wherein the additional data stream detector determines whether at least one of the demodulated transport stream and the equalized transport stream includes the additional data stream.

3. The digital broadcast receiver as claimed in claim 2 , further comprising a decoder which decodes the equalized transport stream to generate decoded data,

wherein the additional data stream detector determines whether the transport stream includes the additional data stream according to whether there is an error in the decoded data.

4. The digital broadcast receiver as claimed in claim 1 , wherein the additional data stream detector determines whether the transport stream includes the additional data stream according to a property code value of the field sync signal.

5. The digital broadcast receiver as claimed in claim 1 , wherein the additional data stream detector determines whether the transport stream includes the additional data stream using a correlation value of a pseudo noise (PN) code inserted into a predetermined symbol of the field sync signal.

6. The digital broadcast receiver as claimed in claim 1 , wherein the additional data stream detector determines whether the transport stream includes the additional data stream according to whether the training signal is in the transport stream.

7. The digital broadcast receiver as claimed in claim 1 , wherein the additional data stream detector generates a channel indicator if the transport stream is determined to include the additional data stream.

8. The digital broadcast receiver as claimed in claim 1 , wherein the training signal is in a data area of the transport stream and is larger than the field sync signal.

9. A stream processing method of a digital broadcast receiver, the method comprising:

receiving a transport stream transmitted from a digital broadcast transmitter;

determining whether the received transport stream includes an additional data stream with an additional error correction coding; and

processing the additional data stream if the transport stream includes the additional data stream,

wherein if the transport stream includes the additional data stream, the transport stream includes a training signal which resets memories used for trellis-encoding at predetermined time, and

wherein the determining comprises determining whether the transport stream includes the additional data stream according to whether forward error correction (FEC) coding is performed with respect to a predetermined symbol of the field sync signal.

10. The stream processing method as claimed in claim 9 , further comprising:

demodulating the received transport stream; and

equalizing the demodulated transport stream,

wherein the determining step determines whether at least one of the demodulated transport stream and the equalized transport stream include the additional data stream.

11. The stream processing method as claimed in claim 10 , further comprising decoding the equalized transport stream to generate decoded data,

wherein the determining step determines whether the transport stream includes the additional data stream according to whether there is an error in the decoded data.

12. The stream processing method as claimed in claim 9 , wherein the determining step determines whether the transport stream includes the additional data stream according to a property code value of the field sync signal.

13. The stream processing method as claimed in claim 9 , wherein the determining step determines whether the transport stream includes the additional data stream using a correlation value of a pseudo noise (PN) code inserted into a predetermined symbol of the field sync signal.

14. The stream processing method as claimed in claim 9 , wherein the determining step determines whether the transport stream includes the additional data stream according to whether the training signal is in the transport stream.

15. The stream processing method as claimed in claim 9 , further comprising, if the transport stream is determined to include the additional data stream, generating a channel indicator.

16. The stream processing method as claimed in claim 9 , wherein the training signal is in a data area of the transport stream and is larger than the field sync signal.