Digital television transmitting system and receiving system and method of processing broadcasting data

A receiving system, comprising:

• a receiving unit for receiving a broadcast signal, in which M number of data groups, which include first error correction encoded first data, and second error correction encoded second data are multiplexed, wherein a size of the M number of data groups is a sum of K bytes (K≧0) of dummy data and (N+2)*(187+P) bytes of a Reed-Solomon (RS) frame including the first data, wherein (N+2) is a number of bytes included in each row of the RS frame, wherein (187+P) is a number of bytes included in each column of the RS frame, wherein N is a number of bytes of the first data included in each row, and wherein P is a number of bytes of RS parity data included in each column;
• a demodulator for demodulating the broadcast signal;
• a block decoder for decoding the first data included in the demodulated broadcast signal in block units;
• and
• at least one RS frame decoder for performing error correction decoding on the block-decoded first data in RS frame units and correcting errors generated in the first data.