摘要:
A system and method for processing a block Low Density Parity Check (LDPC) code are provided. The system includes, a decoding apparatus for decoding a block LDPC code using a parity check matrix, the parity check matrix including an information part and a parity part, the parity part including a first section (B) including a plurality of first permutation matrices, a second section (D) including a second permutation matrix, a third section (T) including a plurality of identity matrices (I) arranged diagonally within the third section and a plurality of third permutation matrices arranged below the plurality of identity matrices, and a fourth section (E) including a fourth permutation matrix.
摘要:
A multiple access scheme is described. One or more encoders are configured to encode a plurality of bit streams using Low Density Parity Check (LDPC) coding. The bit streams correspond to a respective plurality of terminals. The plurality of bit streams are converted to provide a multiple access scheme for the terminals.
摘要:
Systems and methodologies are described that facilitate transmitting low-density parity-check encoded communications in a wireless communications network and incrementing such codes in response to requests from receiving devices. The LDPC codes can have associated constraints allowing the codes to be error corrected upon receipt. The requests for incremented codes can be in cases of low transmission power or high interference, for example, where the original code can be too error-ridden to properly decode. In this case, additional nodes can be added to current and/or subsequent communications to facilitate adding a more complex constraint to the LDPC code. In this regard, the large codes can require less validly transmitted nodes to predict error-ridden values as the additional constraint renders less ambiguity in possible node value choices.
摘要:
The present invention relates to a decoding method and system for stochastic decoding of LDPC codes. Each encoded sample of a set of encoded samples is first scaled by a scaling factor proportional to a noise level of the set of encoded samples. Each of the scaled encoded samples is then converted into a corresponding probability. For each probability a corresponding probability message is the generated by encoding each probability as a sequence of digital bits. Each probability message is then provided to a respective node of a logic circuitry for stochastic decoding. The logic circuitry represents a factor graph of the parity check matrix of the LDPC code. Using the logic circuitry each probability message is processed for determining an estimated sequence of information bits. If an equality node is in a hold state a chosen bit is provided from a corresponding edge memory which is updated by storing output bits from the equality node when the same is in a state other than a hold state.
摘要:
An encoding apparatus derives a bit order based on a puncturing table that specifies different puncturing patterns for different transmission rates. The encoding apparatus then generates an error correcting code from an input information bit string and rearranges the error correcting code in the derived bit order. The error correcting code is punctured by taking a number of consecutive bits from the rearranged error correcting code. The number of bits taken varies depending on the transmission rate. The punctured error correcting code is output to a decoding apparatus, which realigns the code bits according to the transmission rate and the puncturing table, then uses the realigned error correcting code to correct errors in erroneous data. Rearrangement of the error correcting code makes the puncturing process more efficient by avoiding the need to decide whether to take or discard each bit individually.
摘要:
The disclosure proposes bit-error-rate (BER) and symbol-error-rate (SER) estimation techniques and its application to incremental-redundancy and rate-adaptation for modern-coded hybrid-ARQ systems. In particular, BER/SER estimators are proposed based on iterative refinement of mixture-density modeling of the bit/symbol decision metrics. For hybrid-ARQ systems, rate-adaptation functions are proposed based on BER/SER estimators for failed transmissions. Methods are disclosed for code-rate selection based on successfully decoded blocks as well as incremental parity size selection for retransmission of failed blocks Techniques disclosed here apply to forward-error-correction codes employed for digital data communication systems.
摘要:
A method for generating a parity check matrix of a block LDPC code. The parity check matrix includes an information part corresponding to an information word and a first parity part and a second parity part each corresponding to a parity. The method includes determining a size of the parity check matrix based on a coding rate applied when coding the information word with the block LDPC code, and a codeword length; dividing a parity check matrix with the determined size into a predetermined number of blocks; classifying the blocks into blocks corresponding to the information part, blocks corresponding to the first parity part, and blocks corresponding to the second parity part; arranging permutation matrixes in predetermined blocks from among the blocks classified as the first parity part, and arranging identity matrixes in a full lower triangular form in predetermined blocks from among the blocks classified as the second parity part; and arranging the permutation matrixes in the blocks classified as the information part such that a minimum cycle length is maximized and weight values are irregular on a factor graph of the block LDPC code.
摘要:
System and method for designing Slepian-Wolf codes by channel code partitioning. A generator matrix is partitioned to generate a plurality of sub-matrices corresponding respectively to a plurality of correlated data sources. The partitioning is performed in accordance with a rate allocation among the plurality of correlated data sources. A corresponding plurality of parity matrices are generated based respectively on the sub-matrices, where each parity matrix is useable to encode data from a respective one of the correlated data sources.
摘要:
A low density parity check (LDPC) code is used within a wireless apparatus to perform forward error correction (FEC) coding. In at least embodiment of the invention, a (2000, 1600) bit-length LDPC code is used.
摘要:
A channel encoding apparatus using a parallel concatenated low density parity check (LDPC) code. A first LDPC encoder generates a first component LDPC code according to information bits received. An interleaver interleaves the information bits according to a predetermined interleaving rule. A second LDPC encoder generates a second component LDPC code according to the interleaved information bits. A controller performs a control operation such that the information bits, the first component LDPC code which is first parity bits corresponding to the information bits, and the second component LDPC code which is second parity bits corresponding to the information bits are combined according to a predetermined code rate.