This disclosure relates to a 5G or pre-5G communication system for supporting a higher data transfer rate than a 4G communication system such as LTE. The present invention relates to a method for encoding and decoding a channel in a communication or broadcasting system, comprising the steps of: determining an input bit size (CBS); determining a code rate (R); determining a size (Z) of a block; comparing the determined CBS and code rate with predetermined reference values; determining an LDPC sequence to perform LDPC encoding according to the comparison result; and performing LDPC encoding and decoding on the basis of the LDPC sequence and the block size. Further, the present invention comprises the steps of: determining a code rate (R) indicated by a modulation and coding scheme (MCS) index; determining a transport block size; and determining either a first basic matrix or a second basic matrix as a basic matrix on the basis of the transport block size and the code rate.

Embodiments of this application disclose provides a low density parity check (LDPC) channel encoding method for use in a wireless communications system. A communication device encodes an input bit sequence by using a LDPC matrix, to obtain an encoded bit sequence for transmission. The LDPC matrix is obtained based on a lifting factor Z and a base matrix. Embodiments of the application provide eight particular designs of the base matrix. The encoding method provided in the embodiments of the application can be used in various communications systems including the fifth generation (5G) telecommunication systems, and can support various encoding requirements for information bit sequences with different code lengths.

Disclosed are an encoder, a transmitting device, a coding method and a transmission 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 coding is used. A puncture pattern setting unit 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) 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.

The present disclosure relates to a pre-5.sup.th-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). The present invention relates to a method and a device for efficiently shortening and puncturing a non-binary LDPC code, the method for a transmitter shortening and puncturing a non-binary code being capable of supporting various modulation methods by using a single non-binary code, and the method comprising the steps of: shortening, on the basis of a modulation method, at least one information bit in at least one information symbol constituting the non-binary code; encoding the at least one information symbol having a shortened information bit; and puncturing, on the basis of the modulation method, at least one parity code in at least one parity symbol obtained through the encoding step.

A rate matching method for polar codes includes: with respect to polar codes output by an encoder, determining a plurality of types of punching position sets to be selected, punching positions indicated by any two punching position sets being not completely identical to each other; for each type of punching position set, determining the sum of error probabilities of all bit channels for transmitting information bits of the Polar codes when the punching position set is applied, the sum of the error probabilities being called the upper limit of frame error ratios corresponding to the punching position set; and from the plurality of types of punching position sets to be selected, selecting a punching position set corresponding to the minimum upper limit of the frame error ratios as a selected punching position set, and according to p punching positions indicated in the selected punching position set, conducting rate matching,

Examples pertaining to additional bit freezing for polar coding are described. An apparatus performs polar coding to encode a plurality of input subblocks of information bits, frozen bits and optional cyclic redundancy check (CRC) bits to generate a plurality of subblocks of coded bits. The apparatus then transmits at least some of the subblocks of coded bits. In performing the polar coding, the apparatus additionally freezes one of the plurality of input subblocks corresponding to one of the interleaved plurality of subblocks of coded bits which decreases polarization gain due to puncturing.

The device and method disclosed herein are configured for generating a polar code of length N and dimension K on the basis of an original polar code being defined by a code sequence S having N.sub.max bit indices sorted from least reliable to most reliable sub-channels. The device comprises a processing unit configured to: (a) generate an auxiliary code sequence having N.sub.max/2 bit indices by removing bit indices greater than or equal to N.sub.max/2 from the code sequence S; (b) remove from the auxiliary code sequence the last N.sub.R bit indices to generate a modified auxiliary code sequence; and (c) generate the polar code of length N and dimension K by puncturing the original polar code on the basis of a puncturing set defined by the last p=N.sub.max−N bit indices of the modified auxiliary code sequence.

An interleaving method and apparatus are provided, to reduce complexity of implementation processes of polar code interleaving and rate matching. The method includes: obtaining encoded bits after polar code encoding, and sorting the encoded bits based on a priority order of performing a rate matching operation, to obtain a first bit sequence. The first bit sequence includes j subsequences, and j is a positive integer. The method further includes writing the first bit sequence into an interleaver of i rows and j columns. Bits in a column in the interleaver include one of the j subsequences; and reading out bits from the interleaver column by column, until M bits are read. At least two adjacent columns have opposite readout directions, and M is a target code length.

An apparatus for polar coding includes an encoder circuit that implements a transformation C=u.sub.1.sup.N-sB.sub.N-s{tilde over (M)}.sub.n, wherein u.sub.1.sup.N-s, B.sub.N-s, {tilde over (M)}.sub.n, and C are defined over a Galois field GF(2.sup.k), k>1, wherein N=2.sup.n, s<N, u.sub.1.sup.N-s=(u.sub.1, . . . , u.sub.N-s) is an input vector of N−s symbols over GF(2.sup.k), B.sub.N-s is a permutation matrix, {tilde over (M)}.sub.n=((N−s) rows of M.sub.n=), the matrix M.sub.1 is a pre-defined matrix of size q×q, 2<q and N=q.sup.n, and C is a codeword vector of N−s symbols, and wherein a decoding complexity of C is proportional to a number of symbols in C; and a transmitter circuit that transmits codeword C over a transmission channel.

A method, apparatus, and chipset are provided for constructing hybrid automatic repeat request (HARQ) rate-compatible polar codes for communication channels. The method includes constructing, in a terminal, a base polar code of length 2.sup.n; and determining a sequence of m<2.sup.n bits to puncture in the base polar code by testing a predetermined criterion at most (2.sup.2n+2.sup.n)/2−1 times.