A broadcast signal receiver, comprising: a tuner configured to receive the broadcast signal; a synchronization/demodulation module configured to perform channel estimation and synchronization on the broadcast signal by detecting pilots in the broadcast signal, the broadcast signal including a signal frame that includes signaling information; a signaling decoder configured to decode the signaling information, the signaling information including information representing a value of a reducing coefficient k, the signal frame including data symbols carrying data of at least one PLP, wherein a number of carriers for the data symbols is defined based on a Fast Fourier Transform, FFT, size and the reducing coefficient k; a frame parsing module configured to derive the data of at least one PLP by parsing the signal frame based on the signaling information; a demapping and decoding module configured to decode the data of the at least one PLP; and an output processing module configured to process the decoded data outputted from the demapping and decoding module to output one or more streams, wherein: the number of carriers for 8K FFT is 6913 for k=0, 6817 for k=1, 6721 for k=2, 6625 for k=3 and 6529 for k=4, the number of carriers for 16K FFT is 13825 for k=0, 13633 for k=1, 13441 for k=2, 13249 for k=3 and 13057 for k=4, and the number of carriers for 32K FFT is 27649 for k=0, 27265 for k=1, 26881 for k=2, 26497 for k=3 and 26113 for k=4. a tuner configured to receive the broadcast signal; a synchronization/demodulation module configured to perform channel estimation and synchronization on the broadcast signal by detecting pilots in the broadcast signal, the broadcast signal including a signal frame that includes signaling information; a signaling decoder configured to decode the signaling information, the signaling information including information representing a value of a reducing coefficient k, the signal frame including data symbols carrying data of at least one PLP, wherein a number of carriers for the data symbols is defined based on a Fast Fourier Transform, FFT, size and the reducing coefficient k; a frame parsing module configured to derive the data of at least one PLP by parsing the signal frame based on the signaling information; a demapping and decoding module configured to decode the data of the at least one PLP; and an output processing module configured to process the decoded data outputted from the demapping and decoding module to output one or more streams, wherein: the number of carriers for 8K FFT is 6913 for k=0, 6817 for k=1, 6721 for k=2, 6625 for k=3 and 6529 for k=4, the number of carriers for 16K FFT is 13825 for k=0, 13633 for k=1, 13441 for k=2, 13249 for k=3 and 13057 for k=4, and the number of carriers for 32K FFT is 27649 for k=0, 27265 for k=1, 26881 for k=2, 26497 for k=3 and 26113 for k=4. the number of carriers for 8K FFT is 6913 for k=0, 6817 for k=1, 6721 for k=2, 6625 for k=3 and 6529 for k=4, the number of carriers for 16K FFT is 13825 for k=0, 13633 for k=1, 13441 for k=2, 13249 for k=3 and 13057 for k=4, and the number of carriers for 32K FFT is 27649 for k=0, 27265 for k=1, 26881 for k=2, 26497 for k=3 and 26113 for k=4.