The present invention provides a method of transmitting broadcast signals. The method includes, encoding, by an encoder, PLP (Physical Layer Pipe) data; time interleaving, by a time interleaver, the encoded PLP data; frame mapping, by a framer, the time interleaved PLP data onto at least one signal frames; frequency interleaving, by a frequency interleaver, data in the at least one signal frames; and waveform modulating, by a waveform module, the frequency interleaved data in the at least one signal frame and transmitting, by the waveform module, broadcast signals having the modulated data, wherein the frequency interleaving is conducted according to an interleaving mode, wherein the interleaving mode is determined based on a FFT (Fast Fourier Transform) size.

A method and an apparatus for transmitting broadcast signals thereof are disclosed. The apparatus for transmitting broadcast signals, the apparatus comprises an encoder to encode service data corresponding to a number of physical paths, a time interleaver to time interleave the encoded service data in each physical path, a frame builder to build at least one signal frame including the time interleaved service data, a modulator to modulate data in the built at least one signal frame by an OFDM (Orthogonal Frequency Division Multiplex) scheme and a transmitter to transmitting the broadcast signals having the modulated data.

Apparatuses, methods, and systems for interleaving sequential data in time and frequency domains are disclosed. One apparatus includes a processor that interleaves sequential data in time and frequency domains. The sequential data includes a first data occupying a first time-frequency resource and a second data occupying a second time-frequency resource, the second data sequentially follows the first data prior to interleaving, and the first data is separated from the second data by at least one time resource and at least one frequency resource after interleaving.

A broadcast signal transmitter is disclosed. A broadcast signal transmitter according to an embodiment of the present invention comprises an input formatting module configured to perform baseband formatting and to output at least one PLP (Physical Layer Pipe) data; a BICM (Bit Interleaved Coded Modulation) module configured to perform an error correction process on the PLP data; a framing and interleaving module configured to interleave the PLP data and to generate a signal frame; and a waveform generating module configured to generate a broadcast signal by inserting a preamble into the signal frame and performing OFDM modulation.

Disclosed are systems and methods for transmission and reception of data bits. A plurality of data bits are received. FEC-based encoded data bits are generated in accordance with a zipper code framework incorporating component non-binary codes. The zipper code framework includes a buffer having a virtual buffer and a real buffer. Codewords associated with the FEC-based encoded data bits are stored in rows of the real buffer. A given codeword in a given row of the real buffer is mapped to different rows of the virtual buffer in a quasi-diagonal interleaving manner.

The present invention provides a method of transmitting broadcast signals. The method includes, formatting, by an input formatting block, input streams into plural PLPs (Physical Layer Pipes); encoding, by an encoder, data in the plural PLPs; time interleaving, by a time interleaver, the encoded data in the plural PLPs, wherein the time interleaving includes: cell interleaving, by a cell interleaver, the encoded data by permuting cells in a FEC (Forward Error Correction) block in the plural PLPs; frame mapping, by a framer, the time interleaved data onto at least one signal frame; and waveform modulating, by a waveform block, the mapped data in the at least one signal frame and transmitting, by the waveform block, broadcast signals having the modulated data.

A method and an apparatus for transmitting broadcast signals thereof are disclosed. The apparatus for transmitting broadcast signals comprises an encoder for encoding DP (Data Pipe) data corresponding to each of a plurality of DPs, a mapper for mapping the encoded DP data onto constellations, a time interleaver for time interleaving the mapped DP data at DP level, a frame builder for building at least one signal frame including the time interleaved DP data, a modulator for modulating data in the built at least one signal frame by an OFDM (Orthogonal Frequency Division Multiplex) scheme and a transmitter for transmitting the broadcast signals having the modulated data.

A method and an apparatus for transmitting broadcast signals thereof are disclosed. The apparatus for transmitting broadcast signals, the apparatus comprises an encoder to encode service data corresponding to a number of physical paths, a time interleaver to time interleave the encoded service data in each physical path, a frame builder to build at least one signal frame including the time interleaved service data, a modulator to modulate data in the built at least one signal frame by an OFDM (Orthogonal Frequency Division Multiplex) scheme and a transmitter to transmitting the broadcast signals having the modulated data.

A transmitting system, a receiving system, and a method of processing broadcast signals are disclosed. The method for processing a broadcast signal in a broadcast receiver comprises receiving a DTV signal including a data group, the data group including mobile service data, segmented known data sequences, long known data sequences and transmission parameter data, compensating carrier frequency offset of the DTV signal and channel-equalizing the carrier frequency offset compensated DTV signal using at least one of the long known data sequences and segmented known data sequences in the data group of the DTV signal, wherein the channel-equalizing includes performing a Error Correction (FEC) decoding on data located between the segmented known data sequences, and estimating Channel Impulse Response (CIR) using the FEC decoded data as known data.

The present invention provides a method of transmitting broadcast signals. The method includes, formatting, by an input formatting block, input streams into plural PLPs (Physical Layer Pipes); encoding, by an encoder, data in the plural PLPs; time interleaving, by a time interleaver, the encoded data in the plural PLPs, wherein the time interleaving includes: cell interleaving, by a cell interleaver, the encoded data by permuting cells in a FEC (Forward Error Correction) block in the plural PLPs; frame mapping, by a framer, the time interleaved data onto at least one signal frame; and waveform modulating, by a waveform block, the mapped data in the at least one signal frame and transmitting, by the waveform block, broadcast signals having the modulated data.