Abstract: A multidimensional multilevel coding (MLC) encoder comprises a soft forward error correction (FEC) encoder receiving first bits for generating soft FEC encoded bits, a redundancy generator receiving a subset of the soft FEC encoded bits for generating redundant bits, and a hard FEC encoder receiving second bits for generating hard FEC encoded bits. Combinations of the soft FEC encoded bits, the redundant bits, and the hard FEC encoded bits form labels for mapping to a plurality of constellation points. A MLC decoder comprises a redundancy decoder, a soft FEC decoder and a hard FEC decoder. The redundancy decoder combines log-likelihood-ratios (LLR) of soft FEC encoded bits received from the MLC encoder to allow the soft FEC decoder to produce decoded bits. Decoding of hard FEC encoded bits by the hard FEC decoder is conditioned on values of the bits decoded by the soft FEC decoder.

Abstract: A multidimensional multilevel coding (MLC) encoder comprises a soft forward error correction (FEC) encoder receiving first bits for generating soft FEC encoded bits, a redundancy generator receiving a subset of the soft FEC encoded bits for generating redundant bits, and a hard FEC encoder receiving second bits for generating hard FEC encoded bits. Combinations of the soft FEC encoded bits, the redundant bits, and the hard FEC encoded bits form labels for mapping to a plurality of constellation points. A MLC decoder comprises a redundancy decoder, a soft FEC decoder and a hard FEC decoder. The redundancy decoder combines log-likelihood-ratios (LLR) of soft FEC encoded bits received from the MLC encoder to allow the soft FEC decoder to produce decoded bits. Decoding of hard FEC encoded bits by the hard FEC decoder is conditioned on values of the bits decoded by the soft FEC decoder.

Abstract: Embodiments of the present application relate to a method for implementing Turbo equalization compensation. The equalizer divides a first data block into n data segments, where D bits in two adjacent data segments in the n data segments overlap, performs recursive processing on each data segment in the n data segments, before the recursive processing, merges the n data segments to obtain a second data block; and performs iterative decoding on the second data block, to output a third data block, where data lengths of the first data block, the second data block, and the third data block are all 1/T of a code length of a LDPC convolutional code.

Abstract: 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 (Hc) of the time-varying periodic LDPC convolutional code according to the QC-LDPC check matrix; de-blocking, according to requirements of the Hc, data to be coded, and coding data of each sub-block according to the Hc, 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.

Abstract: The present invention provides a decoding method, a decoding apparatus, and a communications system, which implement multi-level coding in a manner combining soft-decision error correction coding and hard-decision error correction coding, implement multi-level decoding in a manner combining soft-decision error correction decoding and hard-decision error correction decoding, so as to integrate advantages of the two manners: compared with a manner in which soft-decision error correction coding and decoding are performed on multiple levels, a manner in which soft-decision error correction coding and decoding are performed on only one level reduces system complexity and resource overhead; and performing hard-decision error correction coding and decoding on other levels on a basis of performing soft-decision error correction coding and decoding on one level ensures gain performance, thereby meeting a gain requirement of a high-speed optical transmission system.

Abstract: The present application discloses a method for processing a signal. An apparatus detects, according to a check relationship set during a forward error correction coding, that a phase jump occurs in a data segment of a signal, and a quantity of degrees of the phase jump, performs, according to the quantity of degrees of the phase jump, a phase correction on the data segment; after the phase correction, performs a confidence correction on the data segment; and after the confidence correction, performs a forward error correction decision decoding on the data segment on which the confidence correction has been performed and output the data segment.

Abstract: The present application discloses a method for processing a signal. An apparatus detects, according to a check relationship set during a forward error correction coding, that a phase jump occurs in a data segment of a signal, and a quantity of degrees of the phase jump; performs, according to the quantity of degrees of the phase jump, a phase correction on the data segment; after the phase correction, performs a confidence correction on the data segment; and after the confidence correction, performs a forward error correction decision decoding on the data segment on which the confidence correction has been performed and output the data segment.

Abstract: Embodiments of the present application relate to a method for implementing Turbo equalization compensation. The equalizer divides a first data block into n data segments, where D bits in two adjacent data segments in the n data segments overlap, performs recursive processing on each data segment in the n data segments, before the recursive processing, merges the n data segments to obtain a second data block; and performs iterative decoding on the second data block, to output a third data block, where data lengths of the first data block, the second data block, and the third data block are all 1/T of a code length of a LDPC convolutional code.

Abstract: The present invention provides a decoding method, a decoding apparatus, and a communications system, which implement multi-level coding in a manner combining soft-decision error correction coding and hard-decision error correction coding, implement multi-level decoding in a manner combining soft-decision error correction decoding and hard-decision error correction decoding, so as to integrate advantages of the two manners: compared with a manner in which soft-decision error correction coding and decoding are performed on multiple levels, a manner in which soft-decision error correction coding and decoding are performed on only one level reduces system complexity and resource overhead; and performing hard-decision error correction coding and decoding on other levels on a basis of performing soft-decision error correction coding and decoding on one level ensures gain performance, thereby meeting a gain requirement of a high-speed optical transmission system.

Abstract: The embodiments of the present invention provide an encoding and decoding method and device. The encoding method includes: equally dividing input K-bit information into n blocks, where k1, k2, . . . , and kn are used to represent each block of information; combining a kith block of information with n?1 encoded code words Vi?1, Vi?2, . . . , and Vi?n+1 of ki?1th, ki?2th, . . . , and ki?n+1th blocks, to obtain a code word to be encoded, where when a sequence number of an encoded code word is smaller than or equal to 0, the encoded code word is history information; performing, by using an LDPC check matrix, encoding on the code word to be encoded, where a generated check bit and the kith block of information form an encoded code word Vi; and outputting encoded code words V1, V2, . . . , and Vn. The embodiments of the present invention are applied in encoding and decoding.

Abstract: 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 (Hc) of the time-varying periodic LDPC convolutional code according to the QC-LDPC check matrix; de-blocking, according to requirements of the Hc, data to be coded, and coding data of each sub-block according to the Hc, 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.

Abstract: Embodiments of the present invention provide a data transmitter, a data receiver, and a frame synchronization method. The data transmitter includes a coding module and a processing module. The coding module is configured to perform forward error correction FEC coding on sent data to obtain an FEC code word, and to output the FEC code word and an indication signal for indicating a boundary position of the FEC code word to the processing module. The processing module is configured to insert a training sequence into the FEC code word according to the indication signal, so that a data receiver determines the boundary position of the FEC code word according to the training sequence.

Abstract: A method, device, and system for polarization division multiplexing (PDM) and polarization division demultiplexing are provided in the field of communication and transmission. The device for polarization division demultiplexing includes a polarization controller (PC), a polarization beam splitter (PBS), a detection control module, an optoelectronic receiver 1, and an optoelectronic receiver 2. The PC is adapted to receive a PDM optical signal carrying an identification signal and perform polarization control on the PDM optical signal. The PBS is adapted to perform polarization division on the PDM optical signal carrying the identification signal after the polarization control. The detection control module is adapted to perform identification signal detection on the optical signal after the polarization division to obtain a power of the identification signal, and output a polarization control signal to control the PC according to a power change of the identification signal.