Disclosed herein is a broadcast signal transmitter. A broadcast signal transmitter according to an embodiment of the present invention includes an input formatting module configured to perform baseband formatting and to output the data of at least one Physical Layer Pipe (PLP), a BICM module configured to perform error-correction processing on the PLP data, a framing and interleaving module configured to interleave the PLP data and to generate a signal frame, and a waveform generation module configured to insert a preamble into the signal frame and to generate a broadcast signal by performing OFDM modulation.