Disclosed is a broadcast signal transmitter. The broadcast signal transmitter includes a first bit interleaved coded modulation (BICM) unit configured to forward error correction (FEC)-encode data of a first layer, a second BICM unit configured to FEC-encode data of a second layer, a layered division multiplexing (LDM) injection unit configured to combine the data of the first layer and the data of the second layer and to output LDM data, a framing and interleaving unit configured to interleave the LDM data and to generate a signal frame, and a waveform generation unit configured to perform OFDM modulation on the LDM data and to generate a broadcast signal.