A method for receiving broadcast signals by an apparatus for receiving broadcast signals, the method includes receiving the broadcast signals having Orthogonal Frequency Division Multiplex (OFDM) symbols including at least one preamble OFDM symbol and at least one data OFDM symbol on which power normalization is performed by using power normalization factors acquired from a frequency domain total power for the OFDM symbols; demodulating the at least one preamble OFDM symbol and the at least one data OFDM symbol into at least one preamble symbol and at least one data symbol by an OFDM scheme; parsing at least one signal frame including the at least one preamble symbol for signaling data and the at least one data symbol for service data; decoding the signaling data; and decoding the service data.