摘要:
Receiving-apparatus employed in MIMO-system includes space-filtering-unit configured to separate receive-signals to signal of first-data-sequence and signal of second-data-sequence on basis of estimation result, provisional-decoding-unit configured to LDPC-decode signal of first-data-sequence and signal of second-data-sequence with check-matrices which is modified in different-forms by fundamental-row-operation from each other, to obtain provisional-likelihood-ratio for first-data-sequence and second-data-sequence, provisional-output-unit configured to output provisional-first-data-sequence and provisional-second-data-sequence on the basis of provisional-likelihood-ratio for first-data-sequence and second-data-sequence respectively, replica-signal-generation-unit configured to generate replica-signal, on basis of provisional-first-data-sequence and provisional-second-data-sequence and estimation-result of propagation-path-estimation-unit, soft-decision-outputting-unit configured to obtain receive-likelihood-values of first-data-sequence and second-data-sequence, on basis of residual-signal obtained by subtracting replica-signal from receive-signals, actual-decoding-unit configured to LDPC-decode receive-likelihood-values, by using the check-matrices, to obtain likelihood-ratio of first-data-sequence and likelihood-ratio of second-data-sequence, and actual-output-unit configured to obtain first-data-sequence and second-data-sequence on the basis of likelihood-ratio of first-data-sequence generated by the actual-decoding-unit and likelihood-ratio of second-data-sequence to hard-decision.
摘要:
A decoder is configured to include an acquisition-unit configured to acquire first respective likelihoods of data-bits and second respective likelihoods of parity-bits, the data-bits and the parity-bits included in code data obtained by LDPC-encoding the data-bits with a low density parity check matrix, a detecting-unit configured to detect reliabilities of the first respective likelihoods and the second respective likelihoods, a forming-unit configured to form an update schedule representing an order of updating the first and second respective likelihoods in order of increasing reliability, in accordance with the reliabilities, an updating-unit configured to update the first and second respective likelihoods in the order represented by the update schedule, with the low density parity check matrix, a discriminating-unit configured to execute hard decision of the likelihoods updated by the updating-unit, and a checking-unit configured to execute parity check of a discrimination result of the discriminating-unit, to obtain the code data.
摘要:
There is provided with a decoding apparatus for decoding a low-density parity check code defined by a parity check matrix, includes: a first operation unit configured to carry out a row operation for each row of the parity check matrix; a calculation unit configured to calculate a reliability coefficient with respect to establishment of a parity check equation defined by said each row, respectively; a second operation unit configured to carry out a column operation for said each row; and a controller configured to iteratively execute one set which includes respective processing by the first operation unit, the calculation unit and the second operation unit and omit the processing by the first operation unit and the calculation unit for a row for which the reliability coefficient has satisfied a threshold.
摘要:
A decoder is configured to include an acquisition-unit configured to acquire first respective likelihoods of data-bits and second respective likelihoods of parity-bits. The data-bits and the parity-bits are included in code data obtained by LDPC-encoding the data-bits with a low density parity check matrix. The decoder also includes a detecting-unit configured to detect reliabilities of the first respective likelihoods and the second respective likelihoods. The decoder also includes a forming-unit configured to form an update schedule representing an order of updating the first and second respective likelihoods in order of increasing reliability, in accordance with the reliabilities. The decoder also includes an updating-unit configured to update the first and second respective likelihoods in the order represented by the update schedule, with the low density parity check matrix. The decoder also includes a discriminating-unit configured to execute hard decision of the likelihoods updated by the updating-unit. The decoder also includes a checking-unit configured to execute parity check of a discrimination result of the discriminating-unit, to obtain the code data.
摘要:
A receiving-apparatus which includes space-filtering-unit configured to separate receive-signals into signal of first-data-sequence and signal of second-data-sequence on basis of estimation result, provisional-decoding-unit configured to LDPC-decode the two corresponding signals, to obtain provisional-likelihood-ratio for the two sequences, provisional-output-unit configured to output two provisional corresponding sequences on the basis of the respective provisional-likelihood-ratio, replica-signal-generation-unit, estimation-result of propagation-path-estimation-unit, soft-decision-outputting-unit configured to obtain receive-likelihood-values of the two sequences, on basis of residual-signal obtained by subtracting replica-signal from receive-signals, actual-decoding-unit configured to LDPC-decode receive-likelihood-values, to obtain likelihood-ratio of the two sequences, and actual-output-unit configured to obtain the two sequences on the basis of likelihood-ratio of the two sequences to hard-decision.
摘要:
Before data is transmitted from a plurality of antennas, a plurality of known symbol sequences are transmitted from these antennas. Each known symbol sequence contains a plurality of known symbols having different subcarrier arrangements. Known symbols transmitted from different antennas have different subcarrier arrangements.
摘要:
Before data is transmitted from a plurality of antennas, a plurality of known symbol sequences are transmitted from these antennas. Each known symbol sequence contains a plurality of known symbols having different subcarrier arrangements. Known symbols transmitted from different antennas have different subcarrier arrangements.
摘要:
A semiconductor memory device includes a semiconductor memory unit which stores LDPC encoded data, and a decoding unit which decodes the encoded data, wherein the decoding unit performs serial decoding using the posterior likelihood ratio as it is for a column element likelihood ratio when the absolute value of the posterior likelihood ratio is not smaller than a threshold and using the column element likelihood ratio as it is for the posterior likelihood ratio when the absolute value of the column element likelihood ratio is not smaller than the threshold, and if the decoding does not succeed even after a predetermined first cycle count of iterative processing is performed or if the number of syndrome errors becomes smaller than a predetermined first syndrome error count, the decoding unit shrinks the absolute values of at least some of posterior likelihood ratios and resets all prior likelihood ratios to “0.”
摘要:
A nonvolatile semiconductor memory system includes a semiconductor memory, at least one first error correction unit and at least one second error correction unit. The semiconductor memory stores a data frame encoded with LDPC codes. The at least one first error correction unit performs a first error correction for the data frame according to a first iterative decoding algorithm. The at least one second error correction unit performs a second error correction for the data frame which is failed to correct error by the at least one first error correction unit. The at least one second error correction unit performs the second error correction according to a second iterative decoding algorithm which uses a message having a larger number of quantization bits than that of the first iterative decoding algorithm.
摘要:
A non-volatile semiconductor memory device comprises a memory cell array including a plurality of memory cells arrayed capable of storing information in accordance with variations in threshold voltage. A likelihood calculator has a plurality of likelihood calculation algorithms for deriving a likelihood value about a stored data bit from a threshold value read out of the memory cell. An error correction unit executes error correction through iterative processing using the likelihood value obtained at the likelihood calculator. A likelihood calculator controller changes among the likelihood calculation algorithms in the likelihood calculator based on a certain value of the number of iterations in the iterative processing obtained from the error correction unit.