This invention presents a method and apparatus for vertical layered finite alphabet iterative decoding of low-density parity-check codes (LDPC) which operate on parity check matrices that consist of blocks of sub-matrices. The iterative decoding involves passing messages between variable nodes and check nodes of the Tanner graph that associated with one or more sub-matrices constitute decoding blocks, and the messages belong to a finite alphabet. Various embodiments for the method and apparatus of the invention are presented that can achieve very high throughputs with low hardware resource usage and power.

The present disclosure relates to low-density parity-check (LDPC) encoding methods and apparatus. One example method includes encoding k information bits by using a submatrix of ((n−k)/Z+j) rows and (n/Z+j) columns at an upper left corner of a check matrix H based on a first transmission code rate R satisfying R=k/(n+j×Z), obtaining a first codeword including the k information bits and (n−k+j×Z) redundant bits, and sending the first codeword to a receive end.

A selective PEG algorithm, creating a sparse matrix while maintaining row weight/column weight at arbitrary multi-levels, and in the process, inactivating an arbitrary edge so that a minimum loop formed between arbitrary nodes is enlarged or performing constrained interleaving, so that encoding efficiency in the case where a matrix space is narrow is improved.

The present invention discloses an erasure code calculation method, including the following steps: S1) splitting original data, and building an original encoding matrix M; S2) acquiring a transverse exclusive OR encoding matrix M1; S3) acquiring a longitudinal exclusive OR encoding matrix M2; S4) acquiring an exclusive OR encoding matrix M3 according to the transverse exclusive OR encoding matrix M1 and the longitudinal exclusive OR encoding matrix M2; S5) transforming a data position of the transverse exclusive OR encoding matrix M1 to acquire a storage matrix M4; S6) judging whether storage nodes at which the last column of data of the storage matrix M4 is stored are damaged; S7) restoring the lost data according to a position 1 of the damaged node; and S8) restoring the lost data according to a position 2 of the damaged node. In the present invention, the operation is rapid, and calculation efficiency is high.

Reduced complexity encoders and related systems, apparatuses, and methods are disclosed. An apparatus includes a data storage device and a processing circuitry. The data storage device is to store a first data part of a transmit data frame. The transmit data frame is received from one or more higher network layers that are higher than a physical layer. The transmit data frame includes the first data part and a second data part. The second data part includes data bits having known values. The processing circuitry is to retrieve the first data part of the transmit data frame from the data storage device and determine parity vectors for the transmit data frame independently of the second data part responsive to the first data part.

A method for encoding information bits with a Q-ary linear error correction code defined over a binary-extension Galois field GF(2.sup.k), and defined by a quasi-cyclic parity-check matrix comprising: first, second and third circulant sub-matrices respectively comprising first, second and third circulants respectively having first, second and third shifts and being defined respectively by first, second and third parameters belonging to the Galois field GF(2.sup.k), said second parameter being the inverse of the first parameter, and the second shift being equal to a difference between a number of rows of each circulant and the first shift. The method comprises determining: a first set of parity-check bits according to a fourth circulant having a fourth shift equal to a difference between said number of rows and said first and third shifts and being defined by the multiplicative inverse of a fourth parameter given by a product between the first and third parameters, and to the second and third circulant sub-matrices, and a second set of parity-check bits according to the determined first set of parity-check bits and said first and second circulant sub-matrices.

A systematic encoder reliably transferring a source data block (SDB) is configured for an outer transform matrix and an inner transform matrix. An inner encoder receives the SDB and generates an output constraint block (OCB) as an SDB image under an inverse of a submatrix of the inner transform matrix. An outer encoder receives a fixed data block (FDB) and the OCB and generates a transform output block (TOB) as a transform input block (TIB) image under the outer transform matrix. The TIB contains the FDB transparently in a sub-block of the TIB, and the TOB contains the OCB transparently in a sub-block of the TOB. The inner encoder receives the TOB and generates a transmitted code block (TCB), transparently containing the SDB in a sub-block therein.

The present disclosure provides techniques for bandwidth constrained communication systems with frequency domain information processing. A bandwidth constrained equalized transport (BCET) communication system can include a transmitter, a communication channel, and a receiver. The transmitter can include a pulse-shaping filter that intentionally introduces memory into a signal in the form of inter-symbol interference, an error control code (ECC) encoder, a multidimensional fast Fourier transform (FFT) processing block and a multidimensional inverse FFT processing block that process the signal in the frequency domain, and a first interleaver. The receiver can include an information-retrieving equalizer, a deinterleaver with an ECC decoder, and a second interleaver joined in an iterative ECC decoding loop. The communication system can be bandwidth constrained, and the signal can comprise an information rate that is higher than that of a communication system without intentional introduction of the memory at the transmitter.

A low-density parity check convolution code (LDPC-CC) is made, and a signal sequence is sent after being subjected to an error-correcting encodement using the low-density parity check convolution code. In this case, a low-density parity check code of a time-variant period (3g) is created by linear operations of first to 3g-th (letter g designates a positive integer) parity check polynomials and input data.

The present technology relates to a transmission device, a transmission method, a reception device, and a reception method for securing good communication quality in data transmission using an LDPC code. LDPC coding for information bits with an information length K=N×r is performed on the basis of an extended parity check matrix having rows and columns extended by a predetermined puncture length L with respect to a parity check matrix of an LDPC code with a code length N of 69120 bits and a coding rate r of 14/16, so that an extended LDPC code having parity bits with a parity length M=N+L−K is generated. A head of the information bits of the extended LDPC code is punctured by L, so that a punctured LDPC code with the code length N of 69120 bits and the coding rate r is generated. The extended parity check matrix includes an A matrix of M1 rows and K columns expressed by a predetermined value M1 and the information length K=N×r, a B matrix of M1 rows and M1 columns, a Z matrix of M1 rows and N+L−K−M1 columns, a C matrix of N+L−K−M1 rows and K+M1 columns, and a D matrix of N+L−K−M1 rows and N+L−K−M1 columns. The present technology can be applied to data transmission and the like using an LDPC code.