The present invention provides a method of transmitting broadcast signals. The method includes, formatting input streams into Data Pipe (DP) data, Low-Density Parity-Check (LDPC) encoding the DP data according to a code rate, bit interleaving the LDPC encoded DP data, mapping the hit interleaved DP data onto constellations, building at least one signal frame including the mapped DP data, and modulating data in the built signal frame by an Orthogonal Frequency Division Multiplexing (OFDM) method and transmitting the broadcast signals having the modulated data, wherein the input streams include Audio/Video (A/V) data and service guide data, and wherein the Audio/Video (A/V) data and service guide data are included in first ISO base media file format (ISOBMFF) files.

A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 64800 and a code rate of 3/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 64-symbol mapping.

A bit interleaving method involves applying a bit permutation process to a QC LDPC codeword made up of N cyclic blocks each including Q bits, and dividing the codeword, after the bit permutation process, into a plurality of constellation words each imade up of M bits, the codeword being divided into N/M sections, each constellation word being associated with one of the N/M sections, and the bit permutation process being performed such that each of the constellation words includes one bit from each of M different cyclic blocks associated with a given section.

A bit interleaver, a bit-interleaved coded modulation (BICM) device and a bit interleaving method are disclosed herein. The bit interleaver includes a first memory, a processor, and a second memory. The first memory stores a low-density parity check (LDPC) codeword having a length of 16200 and a code rate of 4/15. The processor generates an interleaved codeword by interleaving the LDPC codeword on a bit group basis. The size of the bit group corresponds to a parallel factor of the LDPC codeword. The second memory provides the interleaved codeword to a modulator for 64-symbol mapping.

A low density parity check (LDPC) encoder, an LDPC decoder, and an LDPC encoding method are disclosed. The LDPC encoder includes first memory, second memory, and a processor. The first memory stores an LDPC codeword having a length of 16200 and a code rate of 3/15. The second memory is initialized to 0. The processor generates the LDPC codeword corresponding to information bits by performing accumulation with respect to the second memory using a sequence corresponding to a parity check matrix (PCM).

A transmitting apparatus and a receiving apparatus are provided. The transmitting apparatus includes: an encoder configured to generate a low density parity check (LDPC) codeword by LDPC encoding based on a parity check matrix; an interleaver configured to interleave the LDPC codeword; and a modulator configured to map the interleaved LDPC codeword onto a modulation symbol, wherein the modulator is further configured to map a bit included in a predetermined bit group from among a plurality of bit groups constituting the LDPC codeword onto a predetermined bit of the modulation symbol.

A signal receiving method include: demodulating a signal received from a transmitting apparatus to generate values based on 1024-quadrature amplitude modulation (QAM); splitting the values into a plurality of groups; deinterleaving the plurality of groups based on a preset interleaving order; and decoding values of the deinterleaved plurality of groups based on a low density parity check (LDPC) code, a code rate of the LDPC code being 6/15 and a code length of the LDPC code being 64800, wherein the plurality of groups are deinterleaved based on a predetermined equation.

There is provided an apparatus including an acquisition unit that acquires an information block generated from transmission data for a user and subjected to error correction coding, and an interleaving unit that interleaves a bit sequence of the information block using an interleaver unique to the user. The interleaving unit interleaves the bit sequence by interleaving each of two or more partial sequences obtained from the bit sequence.

A parity interleaving apparatus and method for fixed length signaling information are disclosed. A parity interleaving apparatus according to an embodiment of the present invention includes a processor configured to generate a parity bit string for parity puncturing by segmenting parity bits of an LDPC codeword whose length is 16200 and whose code rate is 3/15, into a plurality of groups, and group-wise interleaving the groups using an order of group-wise interleaving; and memory configured to provide the parity bit string for parity puncturing to a parity puncturing unit.

The present technology relates to a transmission method and a reception device for securing favorable communication quality in data transmission using an LDPC code. In group-wise interleaving, the LDPC code with a code length N of 17280 bits is interleaved in units of 360-bit bit groups 0 to 47. In group-wise deinterleaving, a sequence of the LDPC code after group-wise interleaving is returned to an original sequence. The present technology can be applied, for example, in a case of performing data transmission using an LDPC code, and the like.