A descrambler receives data from a memory device. The descrambler calculates a sub-syndrome weight for multiple bits in each of the plurality of descrambled sequences using a set parity check matrix to generate multiple sub-syndrome weights, one for each of the plurality of descrambled sequences. The descrambler selects a sub-syndrome weight among the multiple sub-syndrome weights. The descrambler determines, as a correct scrambler sequence for descrambling the data, a scrambler sequence corresponding to the selected sub-syndrome weight, among the plurality of scrambler sequences.

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 channel encoding method in a communication or broadcasting system is provided. The channel encoding method includes reading a first sequence corresponding to a parity check matrix, converting the first sequence to a second sequence by applying a certain rule to a block size corresponding to a parity check matrix and the first sequence, and encoding information bits based on the second sequence. The block size has at least two different integer values.

Provided are a transmitter and a method for transmitting a data block in a wireless communication system. The method comprises the following steps: deciding the number of bits (s) and encoders (N.sub.ES) to allocate to one axis of a signal constellation; encoding an information bit based on the s and the N.sub.ES and generating a coded block; parsing the coded block based on the s and the N.sub.ES and generating a plurality of frequency sub-blocks; and transmitting the plurality of frequency sub-blocks to a receiver.

If a configuration is employed in which modulation schemes used for an optical communication system can be switched depending on transmission conditions, it is difficult to make effective utilization of frequency resources without the power consumption increasing and the control becoming complex; therefore, an optical transmitter according to an exemplary aspect of the present invention includes an interface means for converting a digital signal to be transmitted under a predetermined transmission condition over an optical carrier wave into a parallel signal with a predetermined bit number at a predetermined transmission rate, and outputting the parallel signal; an encoding means for encoding the parallel signal using one coding system from among a plurality of convolutional coding systems with different degrees of redundancy; a mapping means for mapping an output bit signal output from the encoding means to a modulation symbol; an optical modulation means for modulating the optical carrier wave based on a symbol signal output from the mapping means; and an encoding control means for selecting a predetermined coding system corresponding to the predetermined transmission condition from among the plurality of convolutional coding systems and controlling the interface means, the encoding means, the mapping means, and the optical modulation means in such a way as to operate in accordance with the predetermined coding system.

The present invention is directed to communication systems and methods. In a specific embodiment, the present invention provides a receiver that includes an error correction module. A syndrome value, calculated based on received signals, may be used to enable the error correction module. The error correction module includes an error generator, a Nyquist error estimator, and a decoder. The decoder uses error estimation generated by the Nyquist error estimator to correct the decoded data. There are other embodiments as well.

An operating method of a controller includes: a first step of generating an internal codeword including an ECC unit data and an internal parity code by performing ECC decoding operation to an input data; a second step of updating an external parity code based on the ECC unit data, which is included in the internal codeword currently generated, and the ECC unit data, which is included in the internal codeword previously generated; and a third step of storing in a semiconductor memory device one or more internal codewords and the updated external parity code, which are generated through repetition of the first and second steps, by a unit of predetermined storage size.

An operating method of a controller includes generating error reliability of data based on reliability information of one or more error-corrected bits of the data, wherein the data is read out from a semiconductor memory device and a hard decision ECC decoding to the data through a BCH code is determined as successful; and determining miscorrection of the data based on the error reliability.

A signal compensation method and device, where the method includes receiving a signal sequence suffering from intersymbol interference (ISI), setting a first filtering coefficient to perform filter compensation on the received signal sequence to obtain a first compensation signal sequence, setting a balance filtering coefficient to perform filter compensation on the first compensation signal sequence to obtain a balance compensation result, where the balance filtering coefficient is obtained by adjusting, according to a first compensation error, a balance filtering coefficient set last time, performing sequence estimation on the balance compensation result and outputting the balance compensation result, where the first compensation error adjusts the balance filtering coefficient set to perform filter compensation on the first compensation signal sequence in an iterative manner, thereby effectively compensating for the signal sequence suffering from the ISI, and improving performance of an optical fiber communications system.

Embodiments of the present invention relate to the field of communications, and provide a decoding method and a decoder, which are used to reduce decoding complexity. The method includes: receiving a to-be-decoded signal; performing region decision on the to-be-decoded signal according to a region decision rule formed by S region decision formulas, to acquire a region decision result; acquiring N constellation points according to the decision result, where the N constellation points are separately constellation points that are in the N subsets and that are closest to the to-be-decoded signal; acquiring N non-encoded bits corresponding to the N constellation points, and branch metrics between the to-be-decoded signal and the N constellation points; and performing Viterbi decoding based on the branch metrics and the N non-encoded bits, and outputting a decoding result corresponding to the to-be-decoded signal. The present invention is applicable to a signal decoding scenario.