The described techniques relate to improved methods, systems, devices, or apparatuses that support enhanced efficiency in list Viterbi algorithm (LVA) decoding using iterative comparison trellis construction. Iterative comparison may involve comparison and selection from ordered accumulated path metrics associated with feeding transitions by selecting, for each successive rank of an ordered path metrics list for the current stage, the best unselected accumulated path metric of the feeding transitions. The iterative comparison may be performed sequentially for each stage before processing the next stage. Alternatively, the iterative comparison may be pipelined across stages, and different ranks of the ordered path metrics lists for different stages may be concurrently computed in a single trellis search cycle using multiple comparators. Iterative comparison may be used in an inner decoder to generate an ordered path metrics list for processing according to an error checking function using an outer decoder.

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.

Certain aspects of the present disclosure relate to techniques and apparatus for enhanced decoding, for example, by providing a multi-phase tail biting convolutional code (TBCC) decoding algorithm. An exemplary method generally includes obtaining, via a wireless medium, a codeword encoded with a TBCC encoding scheme, generating metrics for candidate paths through trellis stages of a decoder, propagating information from at least one of the trellis stages to a later trellis stage, while generating the metrics, selecting a set of the candidate paths based on the propagated information, and decoding the encoded codeword by evaluating the selected set of candidate paths based, at least in part, on the generated metrics. Other aspects, embodiments, and features are claimed and described.

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.

A decoding apparatus includes a multi-input branch metric calculation unit configured to calculate, by using a branch label corresponding to a path extending toward a state S at a time point N in a trellis diagram and a plurality of reception signal sequences, a branch metric in the state S, a path metric calculation unit configured to calculate a path metric in the state S at the time point N, and a surviving path list memory configured to store path labels corresponding to L path metrics among a plurality of calculated path metrics. The path metric calculation unit generates a path label in the state S at the time point N by combining the branch label with a path label in each of the states at the time point N−1 and the surviving path list memory outputs path labels corresponding to L path metrics.

[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.

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.

A decoding apparatus (10) includes a multi-input branch metric calculation unit (11) configured to calculate, by using a branch label corresponding to a path extending toward a state S at a time point N in a trellis diagram and a plurality of reception signal sequences, a branch metric in the state S, a path metric calculation unit (12) configured to calculate a path metric in the state S at the time point N, and a surviving path list memory (13) configured to store path labels corresponding to L path metrics among a plurality of calculated path metrics. The path metric calculation unit (12) generates a path label in the state S at the time point N by combining the branch label with a path label in each of the states at the time point N−1 and the surviving path list memory (13) outputs path labels corresponding to L path metrics.

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.

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.