Transmitting system and method for transmitting digital broadcast signal

An apparatus for transmitting broadcast signals, the apparatus comprising:

• an encoder to encode broadcast data using a specific code rate;
• a signaling encoder configured to encode signaling information including transmission parameters, the transmission parameters including code rate information specifying the specific code rate;
• a generating unit configured to generate at least one data frame including the encoded broadcast data and the signaling information;
• and
• a transmission unit configured to transmit the broadcast signals including the at least one data frame,
• wherein the signaling information further includes information specifying a transmission mode,
• wherein the at least one data frame includes a plurality of data units,
• wherein each of the data units includes known data used for channel equalization at a receiver,
• wherein the signaling information further includes information for data units that include the known data,
• wherein a portion of the signaling information is repeated in the at least one data frame, and
• wherein the signaling information further includes information representing whether a current data unit including the known data is concatenated with adjacent data units including the known data.