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.

A processor of an apparatus selects a codebook from a plurality of codebooks embedded in a quasi-cyclic-low-density parity-check (QC-LDPC) code. The processor stores the selected codebook in a memory associated with the processor. The processor also encodes data using the selected codebook to generate a plurality of modulation symbols of the data. The processor further controls a transmitter of the apparatus to multiplex, convert, filter, amplify and radiate the modulation symbols as electromagnetic waves through one or more antennas of the apparatus. In selecting the codebook from the plurality of codebooks embedded in the QC-LDPC code, the processor selects the codebook according to one or more rules such that a small codebook requiring a shorter amount of processing latency for the encoding is selected for the encoding unless a larger codebook corresponding to a larger amount of processing latency for the encoding is necessary for the encoding.

The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). A channel encoding method in a communication or broadcasting system includes identifying an input bit size, determining a block size (Z), determining an LDPC sequence for LDPC encoding, and performing the LDPC encoding based on the LDPC sequence and the block size.

The invention relates to the field of decoders, more specifically, to a decoding method of LDPC (Low Density Parity Check Code). The decoding method comprising: in the rwsr (Row-Wise Scanning Round) phase, the recovery circuit reads a plurality of sign bits, the absolute value of a minimum value, the absolute value of a second smallest value and the absolute value of a third smallest value which are stored previously, and they are output by a comparison and a selector, the output of the comparator and selector is shifted, and then is combined with each sign bit to obtain an update message of the previous check node, the update message is subtracted from the posterior probability by the addition circuit to obtain an input of the update unit.

Aspects of the present disclosure relate to low density parity check (LDPC) coding utilizing a configurable circular buffer for rate matched transmissions. The circular buffer may be configured based on a selected mother code rate and a fixed circular buffer length. For example, the respective sizes of the systematic and parity bit sections of the circular buffer may be variable based on the selected mother code rate.

A method for accelerating bit error correction in a receiver in a radio communication network, wherein the receiver is configured to update soft bit values associated with each code bit of a block code based on parallel parity checks. The method includes receiving a block code encoded message, and for any group of two or more rows of a parity-check matrix of the block code: when the two or more rows are non-overlapping: combining the two or more rows in a row group for parallel updating, updating, in parallel, the parity checks of the row group for the received message, and forming a message estimate based on the updated parity checks. Corresponding computer program product, apparatus, and receiver are also disclosed.

Certain aspects of the present disclosure generally relate to methods and apparatus for decoding low density parity check (LDPC) codes, and more particularly to early termination techniques for low-density parity-check (LDPC) decoder architecture.

Certain aspects of the present disclosure generally relate to methods and apparatus for decoding low density parity check (LDPC) codes, and more particularly to non-linear log-likelihood ratio quantization techniques for low-density parity-check (LDPC) decoder architecture.

Method and system method performed at a wireless transmitting station, including generating a first low density parity check (LPDC) codeword for a first source word for a first transmission, and generating a second LDPC codeword for a retransmission for the first LDPC codeword, the second LDPC codeword including a permutated subset of information bits included in the first LDPC codeword and parity check bits corresponding to the permutated subset of information bits.

A method for constructing a low-density parity-check (LDPC) code using a structured base parity check matrix with permutation matrix, pseudo-permutation matrix, or zero matrix as constituent sub-matrices; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for constructing a LDPC code using a structured base parity check matrix H=[H.sub.d|H.sub.p], H.sub.d is the data portion, and H.sub.p is the parity portion of the parity check matrix; the parity portion of the structured base parity check matrix is such so that when expanded, an inverse of the parity portion of the expanded parity check matrix is sparse; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for encoding variable sized data by using the expanded LDPC code; and applying shortening, puncturing.