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.

This application provides a channel encoding method and a communication apparatus. A second communication apparatus obtains a first parameter of a first communication apparatus, where the first parameter includes a parameter related to channel coding and decoding and a reinforcement learning training parameter. The second communication apparatus determines, based on the first parameter, first code construction information for constructing a coded bit sequence based on an information bit sequence during channel encoding; and after sending the first code construction information to the first communication apparatus, performs channel encoding and decoding on communication data between the first communication apparatus and the second communication apparatus by using the first code construction information to improve channel encoding performance and further improve communication reliability.

A decoding method of low-density parity-check (LDPC) codes based on partial average residual belief propagation includes the following steps: S1: calculating a size of a cluster π in a protograph based on a code length m and a code rate of a target codeword; S2: pre-computing an edge residual r.sub.c.sub.i.sub..fwdarw.v.sub.j corresponding to each edge from a variable node to a check node in a check matrix H; S3: calculating, based on π, a partial average residual (PAR) value corresponding to each cluster in the check matrix H; S4: sorting m/π clusters in descending order of corresponding PAR values, and updating an edge with a largest edge residual in each cluster; S5: updating edge information m.sub.c.sub..fwdarw.v.sub.i from a check node c.sub.i to a variable node v.sub.j, and then updating a log-likelihood ratio (LLR) value L(v.sub.j) of the variable node v.sub.j; and S6: after the updating, making a decoding decision.

A decoding method includes a selection step of reading reception data from a storage unit in units of P words, of reproducing data based on a column weight of a P-column unit of a check matrix, of writing reproduced data into an intermediate value storage unit, and of reading data from as many applicable register files as a row weight on a row block-by-row block basis for row blocks generated by row-wise division of the check matrix; a first shifting step of shifting the data read; a parallel row operation step of performing a row operation in parallel on a word-by-word basis using data shifted; a second shifting step of shifting as many operational results as the row weight, obtained by the row operation, to undo the shifting; and a first update step of updating values in the intermediate value storage unit with operational results.

Methods, systems and devices for forward error correction in orthogonal time frequency space (OTFS) communication systems using non-binary low-density parity-check (NB-LDPC) codes are described. One exemplary method for forward error correction includes receiving data, encoding the data via a non-binary low density parity check (NB-LDPC) code, wherein the NB-LDPC code is characterized by a matrix with binary and non-binary entries, modulating the encoded data to generate a signal, and transmitting the signal. Another exemplary method for forward error correction includes receiving a signal, demodulating the received signal to produce data, decoding the data via a NB-LDPC code, wherein the NB-LDPC code is characterized by a matrix with binary and non-binary entries, and providing the decoded data to a data sink.

According to certain embodiments, a method is provided for fast layered decoding for Low-density Parity-Check (LDPC) codes with a Parity-Check Matrix (PCM) that includes at least a first layer and a second layer. The method includes reading, from a memory, Variable Node (VN) soft information, wherein the VN soft information is associated with a message from a VN to a Check Node (CN) of the second layer of the PCM. A new CN to VN message is calculated from the CN of the second layer of the PCM. New VN soft information is calculated for the VN. The new VN soft information is calculated based on the VN soft information and a new CN to VN message from a CN of the first layer to the VN and an old CN to VN message from the CN of the first layer to the VN such that the updating of new VN soft information is delayed by at least one layer. The fast layered decoding has lower decoding latency and utilizes the decoding hardware more efficiently than standard layered decoding techniques. This may be achieved by keeping the memory access and processing hardware units active simultaneously to avoid excess decoding latency. More specifically, certain embodiments may carry out memory access and computation process simultaneously, without any effort to make the row layers mutually orthogonal to each other. Another technical advantage may be that the proposed decoding algorithm adjusts the LLRs to partially account for deviations from the layered decoding due to non-orthogonal rows.

A method for generating a code, a method for encoding and decoding data, and an encoder and a decoder performing the encoding and decoding are disclosed. In an embodiment, a method for lifting a child code from a base code for encoding and decoding data includes determining a single combination of a circulant size, a lifting function, and a labelled base matrix PCM according to an information length and a code rate using data stored in a lifting table. The lifting table was defined at a code generation stage. The method also includes calculating a plurality of shifts for the child code. Each shift is calculated by applying the lifting function to the labelled base matrix PCM with a defined index using the circulant size and using the derived child PCM to encode or decode data.

Low-density parity-check (LDPC) encoded data with one or more errors is received. Information associated with an early convergence checkpoint that occurs at a fractional iteration count that is strictly greater than 0 and strictly less than 1 is received. The information associated with the early convergence checkpoint is used to perform LDPC decoding on the LDPC encoded data up to the early convergence checkpoint and generate a decoded codeword, wherein the early convergence checkpoint is prior to a first complete iteration of the LDPC decoding. At the early convergence checkpoint that occurs at the fractional iteration count, it is determined whether the LDPC decoding is successful and in the event it is determined that the LDPC decoding is successful, the decoded codeword is output.

Techniques related to improving the error floor performance of a bit flipping (BF) decoder are described. In some examples, error floor performance is improved through determining a set of unreliable check nodes (CNs) and using information about the set of unreliable CNs to compute the flipping energies of variable nodes (VNs). In this manner, the flipping energies can be computed more accurately, thereby lowering the error floor. The set of unreliable CNs can be built through applying various criteria, such as criteria relating to the path length to an unsatisfied CN, the degree of a VN in a path to an unsatisfied CN, and/or checksum value. Path length and VN degree can be applied as selection criteria to determine which CNs qualify as members of the set of unreliable CNs. Checksum value can be applied as a trigger condition for building and/or using the set of unreliable CNs.

Disclosed are an encoder, a transmission device, and an encoding method with which the transmission amount is reduced and a deterioration in transmission efficiency is suppressed while improving reception quality when QC-LDPC or a like block encoding is used. A puncture pattern setting unit (620) searches for a puncture pattern for each integral multiple of the number of columns or for each divisor of the number of columns of a sub block matrix that forms a check matrix (H) of a QC-LDPC code, and a puncture unit (data reduction unit) (630) switches the puncture pattern for each integral multiple of the number of columns or for each divisor of the number of columns of the sub block matrix that forms the check matrix of the QC-LDPC code.