Digital broadcasting system and data processing method
A digital broadcasting system for transmitting/receiving a digital broadcasting signal and a data processing method are disclosed. A program table information has an identifier identifying mobile service data and main service data in a broadcasting signal. The program table information is multiplexed with the mobile service data and main service data. Then, broadcast receiving system can receive and output the mobile service data by parsing the program table information and using the identifier.
1. A method of transmitting a broadcast signal in a transmitter, the method comprising:
pre-processing first service data including audio data or video data for a mobile service via a preprocessor, wherein pre-processing the first service data comprises:
block processing the first service data via a block processor, wherein block processing the first service data comprises:
first converting data bytes of the first service data to data bits via a first converter;
encoding the first converted data bits to output symbols via a first encoder;
symbol interleaving the output symbols via a symbol interleaver;
second converting the symbol interleaved symbols into data bytes of the first service data via a second converter;
forming data groups via a group formatter, each data group including signaling information, known data sequences that have pre-determined values, and the first service data, wherein the signaling information includes information indicating a number of the data groups to be transmitted during a transmission frame, and
forming first service data packets including data in the data groups via a packet formatter;
multiplexing, via a multiplexer, the first service data packets and second service data packets, the second service data packets including second service data including audio data or video data for a main service;
performing, via a second encoder, systematic Reed-Solomon (RS) encoding on the second service data in the multiplexed data packets and non-systematic RS encoding on the first service data in the multiplexed data packets; and
transmitting a broadcast signal including the RS encoded first service data and the RS encoded second service data via a transmission unit,
wherein a collection of the formed data groups is transmitted during slots in the broadcast signal,
wherein the slots are basic time periods for multiplexing of the first service data and the second service data, and
wherein the signaling information includes an identifier of the collection of the formed data groups.
2. The method of claim 1 , wherein:
a code rate of the encoding of the first converted data bits is G/H; and
G and H are integers.
3. The method of claim 2 , wherein the signaling information further includes information indicating the code rate.
4. The method of claim 1 , wherein the pre-processing further comprises first randomizing the first service data via a first randomizer, the method further comprising:
second randomizing the second service data in the second service data packets and only a portion of the first service data packets via a second randomizer.
5. An apparatus for transmitting a broadcast signal, the apparatus comprising:
a pre-processor configured to pre-process first service data including audio data or video data for a mobile service, wherein the pre-processor comprises:
a block processor configured to block process the first service data, wherein the block processor comprises:
a first converter configured to first convert data bytes of the first service data to data bits;
a first encoder configured to encode the first converted data bits to output symbols;
a symbol interleaver configured to symbol interleave the output symbols;
a second converter configured to second convert the symbol interleaved symbols into data bytes of the first service data;
a group formatter configured to form data groups, each data group including signaling information, known data sequences that have pre-determined values, and the first service data, wherein the signaling information includes information indicating a number of the data groups to be transmitted during a transmission frame, and
a packet formatter configured to form first service data packets including data in the data groups;
a multiplexer configured to multiplex the first service data packets and second service data packets, the second service data packets including second service data including audio data or video data for a main service;
a second encoder configured to perform systematic Reed-Solomon (RS) encoding on the second service data in the multiplexed data packets and non-systematic RS encoding on the first service data in the multiplexed data packets; and
a transmission unit configured to transmit a broadcast signal including the RS encoded first service data and the RS encoded second service data,
wherein a collection of the formed data groups is transmitted during slots in the broadcast signal,
wherein the slots are basic time periods for multiplexing of the first service data and the second service data, and
wherein the signaling information includes an identifier of the collection of the formed data groups.
6. The apparatus of claim 5 , wherein:
a code rate of the first encoder is G/H; and
G and H are integers.
7. The apparatus of claim 6 , wherein the signaling information further includes information indicating the code rate.
8. The apparatus of claim 5 , wherein the pre-processor further comprises a first randomizer configured to first randomize the first service data, the apparatus further comprising:
a second randomizer configured to second randomize the second service data in the second service data packets and only a portion of the first service data packets.