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 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 2/15. 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.

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.

Methods, apparatus, and systems that relate to rate matching scheme design for polar coding, PAC coding, or other pre-transformed polar coding are described. One example method includes determining, by a first node, an output bit sequence having E bits based on an input bit sequence having K bits, wherein the output bit sequence is determined by 1) performing a polar transform with H components and 2) performing either no pre-transform or at least two pre-transform operations; wherein the polar transform is based on H polar matrices G.sup.(N.sup.0.sup.), G.sup.(N.sup.1.sup.), . . . , G.sup.(N.sup.H1.sup.), wherein H, K and E are integers greater than 1, wherein a polar matrix G.sup.(N.sup.i.sup.) is of size N.sub.i. The method also includes transmitting, by the first node, a signal including the output bit sequence to a second node.

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 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 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 16-symbol mapping.

Multiple data permutation operations in respective different dimensions are used to provide an overall effective data permutation using smaller blocks of data in each permutation than would be used in directly implementing the overall permutation in a single permutation operation. Data that has been permuted in one permutation operation is block interleaved, and the interleaved data is then permuted in a subsequent permutation operation. A matrix transpose is one example of block interleaving that could be applied between permutation operations.

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 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 16-symbol mapping.

Methods, apparatus, and systems that relate to rate matching scheme design for polar coding, PAC coding, or other pre-transformed polar coding are disclosed. In one example aspect, a method for digital communication includes determining, by a first node, an output bit sequence having E bits based on an input bit sequence c having K bits, wherein the output bit sequence is determined based on an output of a polar transform and an output of a repetition operation, and wherein the input of the repetition operation is a portion of a bit sequence before the polar transform. The method also includes transmitting, by the first node, a signal including the output bit sequence to a second node.

Multiple data permutation operations in respective different dimensions are used to provide an overall effective data permutation using smaller blocks of data in each permutation than would be used in directly implementing the overall permutation in a single permutation operation. Data that has been permuted in one permutation operation is block interleaved, and the interleaved data is then permuted in a subsequent permutation operation. A matrix transpose is one example of block interleaving that could be applied between permutation operations.