An optical transmission system including an optical transmitter and an optical receiver, wherein the optical transmitter includes a signal coding unit that performs non-linear block coding on an M (M is an integer greater than or equal to 1)-value symbol sequence or a bit sequence input as data information to generate an L (L is an integer greater than or equal to 2, L>M)-value symbol sequence that corresponds to the M-value symbol sequence or the bit sequence in one-to-one correspondence, a digital-to-analog conversion unit that converts the generated L-value symbol sequence to an analog signal, and a modulator that generates an optical modulation signal by performing modulation based on the analog signal, and the optical receiver includes a light receiving unit that receives the optical modulation signal transmitted from the optical transmitter and converts the optical modulation signal to an electrical signal, and a signal decoding unit that restores the M-value symbol sequence or the bit sequence by performing processing that is the reverse of processing performed by the signal coding unit, on the electrical signal.

An optical transmission system including an optical transmitter and an optical receiver, wherein the optical transmitter includes a signal coding unit that performs non-linear block coding on an M (M is an integer greater than or equal to 1)-value symbol sequence or a bit sequence input as data information to generate an L (L is an integer greater than or equal to 2, L>M)-value symbol sequence that corresponds to the M-value symbol sequence or the bit sequence in one-to-one correspondence, a digital-to-analog conversion unit that converts the generated L-value symbol sequence to an analog signal, and a modulator that generates an optical modulation signal by performing modulation based on the analog signal, and the optical receiver includes a light receiving unit that receives the optical modulation signal transmitted from the optical transmitter and converts the optical modulation signal to an electrical signal, and a signal decoding unit that restores the M-value symbol sequence or the bit sequence by performing processing that is the reverse of processing performed by the signal coding unit, on the electrical signal.

A convolutional decoder includes a first storage, a second storage, a branch metric processor to determine branch metrics for transitions of states from a start step to a last step according to input bit streams, an ACS processor to select maximum likelihood path metrics to determine a survival path according to the branch metrics and to update states of the start step to the first storage and the second storage alternately based on the selection of the maximum likelihood path metrics, and a trace back logic to selectively trace back the survival path based on the states of the start step stored in a selected storage among the first storage and the second storage.

A device generates a symbol sequence by performing adaptive equalization by an estimation inverse transfer function of a transmission line on a reception signal sequence extracted from the transmission line, and performing provisional determination on the symbol sequence generated; generates a plurality of the symbol sequences indicating transmission line states in a range of a provisional determination symbol provisionally determined and nearby symbols of the provisional determination symbol; generates, based on the plurality of the symbol sequences indicating the transmission line states generated and an estimation transfer function of the transmission line, an estimation reception symbol sequence for each of the transmission line states; calculates a metric between the symbol sequence obtained from the reception signal sequence and each of a plurality of the estimation reception symbol sequences; selects a most likelihood estimation reception symbol sequence of the plurality of the estimation reception symbol sequences, based on the calculated metric, the provisional determination symbol, and the nearby symbols of the provisional determination symbol; and determines a transmission symbol sequence.

Provided are a bit flipping device and method and a computer readable program for the same. The bit flipping device for input data having a two-dimensional array pattern includes: a clustering unit configured to generate at least one input data sequence based on the two-dimensional array pattern of the input data and classify the input data sequence into at least one cluster according to a preset method; and a bit flipping unit configured to perform bit flipping on erroneous bits in the input data sequence based on the classified cluster. Therefore, it is possible to further reduce inefficiency while further reducing system complexity compared to the existing error correction code-based bit flipping method by coupling the bit flipping device to an output side of a partial response maximum likelihood (PRML) detector to classify an output value of the PRML detector into at least one cluster and perform bit flipping based on the classified result.

A method comprises: receiving, from a communication channel, non-binary multilevel symbols that represent corresponding multibit labels each including at least a least-significant bit (LSB) and a most-significant bit (MSB), the non-binary multilevel symbols mapped to the multibit labels according to set-partition labeling, which partitions the non-binary multilevel symbols between a first set and a second set according to a first value and a second value of the LSB, respectively; digitizing the non-binary multilevel symbols to produce symbol samples; and performing Soft-Output-Viterbi (SOV) equalization of the non-binary multilevel symbols based on the symbol samples, to produce decoded symbol information corresponding to the non-binary multilevel symbols.

A method comprises: receiving, from a communication channel, non-binary multilevel symbols that represent corresponding multibit labels each including at least a least-significant bit (LSB) and a most-significant bit (MSB), the non-binary multilevel symbols mapped to the multibit labels according to set-partition labeling, which partitions the non-binary multilevel symbols between a first set and a second set according to a first value and a second value of the LSB, respectively; digitizing the non-binary multilevel symbols to produce symbol samples; and performing Soft-Output-Viterbi (SOV) equalization of the non-binary multilevel symbols based on the symbol samples, to produce decoded symbol information corresponding to the non-binary multilevel symbols.

Example systems, read channels, and methods provide bit value detection from an encoded data signal using a neural network soft information detector. The neural network detector determines a set of probabilities for possible states of a data symbol from the encoded data signal. A soft output detector uses the set of probabilities for possible states of the data symbol to determine a set of bit probabilities that are iteratively exchanged as extrinsic information with an iterative decoder for making decoding decisions. The iterative decoder outputs decoded bit values for a data unit that includes the data symbol.

Aspects of the disclosure provide for methods and systems for Sub-codebook based Trellis Coded Quantization for CSI Feedback. An aspect of the disclosure provides method executed by a receiver. The method includes receiving a signal from a transmitter, via a communication channel between the receiver and the transmitter. The method further includes estimating parameters associated with the channel based on the received signal. The method further includes obtaining phase information from the estimated parameters. The method further includes applying a trellis coded quantization (TCQ) scheme to the obtained phase information by mapping each sub-codebook index of a set of sub-codebook indices to output bits of each trellis branch making the distance between sub-codebooks maximally equal. The method further includes transmitting a channel state information (CSI) measurement feedback to the transmitter, the CSI measurement feedback based on the TCQ scheme and comprising one or more of: a beginning state, input bits to the TCQ scheme, and a sub-codebook index.

A class-labeled span sequence identification apparatus includes a span generation unit that generates all spans generable from a unit sequence input, a calculation unit that calculates a probability that each of the spans belongs to an individual class of a plurality of predefined classes, and an identification unit that identifies, from among span sequences generable in accordance with the spans, a class-labeled span sequence having a maximum product of a plurality of the probabilities or a maximum sum of scores according to the plurality of the probabilities, and thereby, improves accuracy of a class segmentation position in the unit sequence.