The present disclosure relates to a pre-5.sup.th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4.sup.th-Generation (4G) communication system such as Long Term Evolution (LTE). A method of decoding a signal in a communication system includes receiving an encoded bit-stream corresponding to message bits and first Cyclic Redundancy Check (CRC) bits, obtaining a codeword through a traceback for at least part of the encoded bit-stream, generating second CRC bits by performing CRC encoding on the codeword, and performing decoding based on at least part of the second CRC bits.

Devices, systems and methods for convolutional precoding and decoding of polar codes are disclosed. An example method for error correction in a data processing system includes receiving a noisy codeword, the codeword having been generated based on an outer stream decodable code and an inner polar code and provided to a communication channel or a storage channel prior to reception by the decoder, the stream decodable code characterized by a trellis, and performing, based on the trellis, a list-decoding operation on the noisy codeword vector to generate a plurality of information symbols, the list-decoding operation being configured to traverse through a plurality of states at one or more stages of a plurality of decoding stages.

[Problem] Encoding and decoding techniques capable of speeding up an error-correction decoding process utilizing channel polarization are provided.

[Solution] In an encoding device, the information bit sequence is input on division for each designated bit length; error-correction encoding is performed on an information block of the designated bit length to generate L M-bit codes, each M-bit code having a predetermined bit length M; the L M-bit codes are converted into M L-bit blocks each having a predetermined bit length of L; the M L-bit blocks are Polar-converted to M L-bit codes, each L-bit code having a bit length of L, through channel polarization processing; and division of the information bit sequence is determined based on channel polarization information.

A decoding device includes a decode processing unit and a data temporary saving unit holding, of reception data to be input to the decode processing unit, a first number of pieces of reception data from a beginning of a frame and outputting the reception data being held after completion of inputting of one frame of the reception data to the decode processing unit. The decode processing unit includes a branch metric calculation unit, an ACS calculation unit calculating path metrics of the survivor paths based on the branch metric, a survivor path storage unit storing and holding a value determined based on each survivor path in each corresponding one of shift registers associated with the states, and an output selection unit outputting, among values output from the shift registers, a value associated with a path metric having the maximum likelihood among current path metrics, as a decoding result.

Certain aspects of the present disclosure relate to techniques and apparatus for increasing decoding performance and/or reducing decoding complexity. A transmitter may divide data of a codeword into two or more sections and then calculate redundancy check information (e.g., a cyclic redundancy check or a parity check) for each section and attach the redundancy check information to the codeword. A decoder of a receiver may decode each section of the codeword and check the decoding against the corresponding redundancy check information. If decoding of a section fails, the decoder may use information regarding section(s) that the decoder successfully decoded in re-attempting to decode the section(s) that failed decoding. In addition, the decoder may use a different technique to decode the section(s) that failed decoding. If the decoder is still unsuccessful in decoding the section(s), then the receiver may request retransmission of the failed section(s) or of the entire codeword.

Methods and apparatuses are provided for operating a list Viterbi decoder. A path metric difference (PMD) threshold is set based on an input signal level and a PMD limit value. Decoding is performed by using the PMD threshold. Performing the decoding includes determining a PMD of a best path, comparing the determined PMD and the PMD threshold, and declaring a decoding failure and ending performing of the decoding, if the PMD is greater than or equal to the PMD threshold.

Certain aspects of the present disclosure relate to techniques and apparatus for increasing decoding performance and/or reducing decoding complexity. An exemplary method generally includes receiving, via a wireless medium, a codeword encoded using a tailless convolutional code (TLCC) with a known start state, evaluating a set of decoding candidate paths through a trellis decoder that originate at the known start state of the TLCC, performing, for each of a plurality of the decoding candidate paths, a back trace from a respective end state to the known start state, and selecting one of the decoding candidate paths based, at least in part, on path metrics generated while performing the back trace. Other aspects, embodiments, and features are also claimed and described.

Disclosed in some examples are methods, systems, devices, and machine-readable mediums which provide for an enhanced decoding system that utilizes a variable sequence decoding to demultiplex data streams at a receiver. For example, the receiver may utilize an erasures decoding when the number of unknown bits, such as dissimilar transmitted bits (e.g., 1 0 or 0 1), is below a threshold (which may be the Hamming distance D-1). Otherwise, if the number of dissimilar transmitted bits is above the threshold, a list decoding is utilized. If the list decoding does not produce a single result, but instead produces multiple possible results, selection logic may be employed. The selection logic may utilize an errors and erasures decoding of the possible results, a media decoding of the possible results, and/or the like.

Embodiments of the present invention disclose a channel decoding method, apparatus, and system. The channel decoding apparatus includes a memory storing instructions; and a processor coupled to the memory to execute the instructions to: obtain decoding information of first channel decoding of a data block; determine whether the first channel decoding fails; in response to determining that the first channel decoding fails, obtain a reference sequence number of the data block; obtain at least one matching historical demodulated soft value; combine the demodulated soft value of the data block and the at least one matching historical demodulated soft value to obtain a combined demodulated soft value of the data block; and perform second channel decoding on the combined demodulated soft value of the data block.

A method for processing a digital signal includes: receiving a plurality of protocol data units, each having a header including a plurality of control word bits; and a plurality of audio frames, each including a cyclic redundancy check code; decoding the protocol data units using an iterative decoding technique, wherein the iterative decoding technique uses a soft output decoding algorithm for iterations after the first iteration; and using decoded cyclic redundancy check codes to flag the audio frames containing errors. A receiver that implements the method is also provided.