A pre-5th-generation (pre-5G) or 5G communication system for supporting higher data rates beyond a 4th-generation (4G) communication system, such as long term evolution (LTE) is provided. A channel encoding method in a communication or broadcasting system includes identifying an input bit size, determining a block size (Z), determining a low density parity check (LDPC) sequence to perform LDPC encoding, and performing the LDPC encoding based on the LDPC sequence and the block size.

An apparatus and method are described. The apparatus includes a transceiver and processor, which attach transport block (TB) level CRC bits to a TB, select an LDPC base graph (BG) based on a code rate (CR) and TB size of the TB including TB level CRC bits, determine a number of code blocks (CBs) to use for segmenting the TB including TB level CRC bits depending on the selected LDPC BG, determine a single CB size for each of the CBs based on the number of CBs, segment the TB including TB level CRC bits into the CBs based on the number of CBs and CB size, pad zeros to a last CB of the CBs in the segmented TB, attach CB level CRC bits to each CB in the segmented TB, encode each CB in the segmented TB using the selected LDPC base graph, and transmit the encoded CBs.

This application discloses a method and an apparatus for processing information, a communications device, and a communications system. The communications device is configured to obtain a starting position of an output bit sequence in a coded block in a circular buffer, and determine the output bit sequence in the coded block based on a length of the output bit sequence and the starting position. A value of the starting position is one of {p.sub.0, p.sub.1, p.sub.2, . . . , p.sub.k.sub.max .sub.−1}, where 0≤p.sub.k <N.sub.CB, p.sub.k is an integer, k is an integer, 0≤k<k.sub.max , N .sub.CB is a size of the coded block, and k.sub.max is an integer greater than or equal to 4.

This application relates to communicating information between communication devices. A channel coding method is disclosed. A communication device obtains an input sequence of K bits. The communication device encodes the input sequence using a low density parity check (LDPC) matrix H, to obtain an encoded sequence. The LDPC matrix H is determined according to a base matrix and a lifting factor Z. The base matrix includes m rows and n columns, m is greater than or equal to 5, and n is greater than or equal to 27. The lifting factor Z satisfies a relationship of 22*Z≥K. According to the encoding method provided in the embodiments, information bit sequences of a plurality of lengths can be encoded for transmission between the communication devices.

A receiver is provided. The receiver includes: a first decoder configured to decode a superposition-coded signal by using a parity check matrix to generate Low Density Parity Check (LDPC) information word bits and first parity bits corresponding to a first layer signal; an encoder configured to encode the LDPC information word bits and the first parity bits to generate second parity bits, or encode the LDPC information word bits to generate the first parity bits and the second parity bits, by using the parity check matrix; and a second decoder configured to decode a signal which is generated by removing the first layer signal, corresponding to the LDPC information word bits, the first parity bits, and the second parity bits, from the superposition-coded signal, to reconstruct bits transmitted through the second layer signal.

A parity interleaving apparatus and method for variable 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.

Certain aspects of the present disclosure generally relate to techniques for puncturing of structured low-density parity-check (LDPC) codes. Certain aspects of the present disclosure generally relate to methods and apparatus for a high-performance, flexible, and compact LDPC code. Certain aspects can enable LDPC code designs to support large ranges of rates, blocklengths, and granularity, while being capable of fine incremental redundancy hybrid automatic repeat request (IR-HARD) extension while maintaining good floor performance, a high-level of parallelism to deliver high throughout performance, and a low description complexity.

This application discloses a method and an apparatus for processing information, a communications device, and a communications system. The communications device is configured to obtain a starting position of an output bit sequence in a coded block in a circular buffer, and determine the output bit sequence in the coded block based on a length of the output bit sequence and the starting position. A value of the starting position is one of {p.sub.0, p.sub.1, p.sub.2, . . . , p.sub.k.sub.max.sub.−1}, where 0≤p.sub.k<N.sub.CB, p.sub.k is an integer, k is an integer, 0≤k<k.sub.max, N.sub.CB is a size of the coded block, and k.sub.max is an integer greater than or equal to 4.

A method may comprise transmitting a first signal derived from a first subset of a set of LDPC coded bits and transmitting a second signal derived from a second subset of the set of LDPC coded bits. The second subset may be selected from the set of LDPC coded bits based on a lifting size of an LDPC base graph. The method may further comprise receiving an indication of a first redundancy version. The transmitting the first signal may be in response to receiving the indication of the first redundancy version.

Provided is an encoding method and device and a decoding method and device for structured LDPC. The encoding method includes: determining a base matrix used for encoding and performing an LDPC encoding operation on a source information bit sequence according to the base matrix and an expansion factor Z corresponding to the base matrix to obtain a codeword sequence, where Z is a positive integer. The base matrix includes multiple submatrices and the submatrices include an upper-left submatrix Hb1 and an upper-left submatrix Hb2, and the upper-left submatrix Hb1 is an upper-left submatrix of the upper-left submatrix Hb2.