A loss correction encoding device having an improved capability of loss correction using LDPC-CC includes a rearranging unit that rearranges information data contained in n information packets according to the constraint length Kmax and the encoding rate (q1)/q of a check polynomial of the loss correction code used in a loss correction encoding unit. Specifically, the rearranging unit rearranges the information data in such a way that continuous Kmax(q1) pieces of information data after rearrangement are contained in different information packets. The rearranging unit distributes the information data to information blocks from n information packets, where n satisfies the formula Kmax(q1)n.

Methods and apparatuses for coding a codeword. An apparatus for decoding the codeword includes a memory configured to receive the codeword encoded based on a low-density parity check (LDPC) code H-matrix and a two-step lifting matrix and processing circuitry configured to decode the received codeword. An apparatus for encoding the codeword includes memory configured to store information bits to be encoded into the codeword and processing circuitry configured to encode the codeword based on based on a LDPC code H-matrix and a two-step lifting matrix. A code length of the LDPC code H-matrix lifted by the two-step lifting matrix is an integer multiple of 672 bits. The LDPC code block H-matrix may be an IEEE 802.11ad standard LDPC coding matrix. The two-step lifting matrix can be one of a plurality of two-step lifting matrices to generate a family of LDPC codes.

The present invention discloses a coding and decoding method, apparatus, and system for forward error correction, and pertains to the field of communications. The method includes: determining check matrix parameters of time-varying periodic LDPC convolutional code according to performance a transmission system, complexity of the transmission system, and a synchronization manner for code word alignment, constructing a QC-LDPC check matrix according to the determined check matrix parameters, and obtaining a check matrix (H.sub.c) of the time-varying periodic LDPC convolutional code according to the QC-LDPC check matrix; de-blocking, according to requirements of the H.sub.c, data to be coded, and coding data of each sub-block according to the H.sub.c, so as to obtain multiple code words of the LDPC convolutional code; and adding the multiple code words of the LDPC convolutional code in a data frame and sending the data frame.

LDPC coding is executed using a check matrix of an LDPC code whose code length is 736 bits and whose code rate is 1/4, and modulation is executed using a repetition unit that has an LDPC code obtained by the LDPC coding, repeatedly arranged therein. The LDPC code includes information bits and parity bits, the check matrix includes an information matrix portion corresponding to the information bits and a parity matrix portion corresponding to the parity bits, the parity matrix portion has a stepwise structure, the information matrix portion is indicated by a check matrix initial value table, and the check matrix initial value table is a predetermined table indicating positions of elements of 1 of the information matrix portion for each eight columns. This technique is applicable to, for example, information transmission using the LDPC code.

Systems and methods herein provide for error correction via Low Density Parity Check (LDPC) coding. In one embodiment, a system includes a data buffer operable to receive a block of Low Density Parity Check (LDPC) encoded data. The system also includes a processor operable to reduce a belief propagation algorithm used to encode the LDPC encoded data into a quadratic polynomial, to embed the quadratic polynomial onto a plurality of quantum bits (qubits), and to decode the block of LDPC encoded data via the qubits.

Techniques for improving the bit error rate (BER) performance of an error correction system are described. In an example, the error correction system implements low-density parity-check (LDPC) decoding that uses bit flipping. In a decoding iteration, a feature map is generated for a bit of an LDPC codeword. The bit corresponds to a variable node. The feature map is input to a neural network that is trained to determine whether bits should be flipped based on corresponding feature maps. An output of the neural network is accessed. The output indicates that the bit should be flipped based on the feature map. The bit is flipped in the decoding iteration based on the output of the neural network.

An encoding method and encoder of a time-varying LDPC-CC with high error correction performance are provided. In an encoding method of performing low density parity check convolutional coding (LDPC-CC) of a time varying period of q using a parity check polynomial of a coding rate of (n1)/n (where n is an integer equal to or greater than 2), the time varying period of q is a prime number greater than 3, the method receiving an information sequence as input and encoding the information sequence using Equation 1 as a g-th (g=0, 1, . . . , q1) parity check polynomial to satisfy 0.

An apparatus and method for generating a broadcast signal frame corresponding to a time interleaver supporting a plurality of operation modes are disclosed. An apparatus for generating broadcast signal frame according to an embodiment of the present invention includes a combiner configured to generate a multiplexed signal by combining a core layer signal and an enhanced layer signal at different power levels; a power normalizer configured to reduce the power of the multiplexed signal to a power level corresponding to the core layer signal; a time interleaver configured to generate a time-interleaved signal by performing interleaving that is applied to both the core layer signal and the enhanced layer signal; and a frame builder configured to generate a broadcast signal frame including a preamble for signaling time interleaver information corresponding to the time interleaver, the time interleaver uses one of time interleaver groups, and the time interleaver performs the interleaving by using one of a plurality of operation modes.

A loss correction encoding device having an improved capability of loss correction using LDPC-CC includes a rearranging unit that rearranges information data contained in n information packets according to the constraint length Kmax and the encoding rate (q1)/q of a check polynomial of the loss correction code used in a loss correction encoding unit. Specifically, the rearranging unit rearranges the information data in such a way that continuous Kmax(q1) pieces of information data after rearrangement are contained in different information packets. The rearranging unit distributes the information data to information blocks from a information packets, where n satisfies the formula Kmax(q1)n.

Systems, apparatuses and methods may provide for technology to receive a codeword containing an SC-LDPC code and conduct a min-sum decode of the SC-LDPC code based on a plurality of scaling factors. In an embodiment, the scaling factors are non-uniform across check nodes and multiple iterations of the min-sum decode.