Disclosed is an apparatus for transmitting a broadcast signal, including: an input formatting module configured to demultiplex an input stream into at least one Data Pipe (DP); a BICM (Bit Interleaved Coding and Modulation) module configured to perform error correction processing on data of the DP; a frame building module configured to map the data of the DP to symbols within a frame; an OFDM generation module configured to generate a transmission signal by inserting a preamble into the frame and performing OFDM modulation; and a transmission parameter control module configured to set at least one transmission parameter and control transmission signal processing of the frame building module and the OFDM generation module.