A method for encoding bits according to a convolutional code. Bits to be encoded with the convolutional code are obtained for transmission over a communication channel. The bits are encoded according to the convolutional code with an encoder having an M-bit memory and a plurality of logic gates so as to separate trellis segments of the convolutional code into trellis sub-segments having a reduced number of branches per state than that of the trellis segments.

A receiver includes a polar decoder for decoding an encoded codeword transmitted over a communication channel The receiver includes a front end to receive over a communication channel a codeword including a sequence of bits modified with noise of the communication channel and a soft decoder operated by a processor to produce a soft output of the decoding. The codeword is encoded by at least one polar encoder with a polar code. The processor is configured to estimate possible values of the bits of the received codeword using a successive cancelation list (SCL) decoding to produce a set of candidate codewords, determine a distance between each candidate codeword and a soft input to the soft decoder, and determine a likelihood of a value of a bit in the sequence of bits using a difference of distances of the candidate codewords closest to the received codeword and having opposite values at the position of the bit.

A transmitter for transmitting an encoded codeword over a communication channel includes a source to accept source data, an irregular polar encoder operated by a processor to encode the source data with at least one polar code to produce the encoded codeword, a modulator to modulate the encoded codeword, and a front end to transmit the modulated and encoded codeword over the communication channel. The polar code is specified by a set of regular parameters including one or combination of parameters defining a number of data bits in the codeword, a parameter defining a data index set specifying locations of frozen bits in the encoded codeword, and a parameter defining a number of parity bits in the encoded codeword. The polar code is further specified by a set of irregular parameters including one or combination of parameters defining an irregularity of values of at least one regular parameter of the polar code, a parameter defining an irregularity of permutation of the encoded bits, a parameter defining an irregularity of polarization kernels in the polar code, and a parameter defining an irregularity in selection of de-activated exclusive-or operations on different stages of the polar encoding, and wherein the irregular polar encoder encodes the codeword using the regular and the irregular parameters of the polar code.

Calculating path metrics, associated with respective states of an n-state trellis, by accumulating branch metrics in a sequence detector. Each path metric is represented by N bits plus a wrap-around bit for indicating wrap-around of the N-bit value of that path metric.

Systems, devices, and methods for encoding information bits for storage, including obtaining information bits and a target constraints vector, placing the information bits in an input vector, setting balance bits included in the input vector to zero, encoding the input vector using a systematic code to obtain a preliminary codeword, applying a constraints matrix to the preliminary codeword to obtain a preliminary constraints vector, applying a transition matrix to a sum of the preliminary constraints vector and the target constraints vector to determine updated balance bits, obtaining an output codeword based on the information bits and the updated balance bits, and storing the output codeword in the storage device.

An apparatus and a method. The apparatus includes a receiver to receive a polar codeword of length m.sup.j; a processor configured to determine a decoding node tree structure with m.sup.j leaf nodes for the received codeword, and receive i indicating a level at which parallelism of order m is applied to the decoding node tree structure, wherein i indicates levels of the decoding node tree structure, and wherein the m.sup.j leaf nodes are at level j; and m successive cancellation list decoders (SCLDs) applied to each child node of each node in the decoding node tree structure at level i1, wherein each of the m SCLDs executes in parallel to determine log likelihood ratios (LLRs) for a codeword of length m.sup.ji, and wherein each of the m SCLDs uses LLRs of an associated parent node without using a hard decision or a soft reliability estimate of any other node of the other m SCLDs.

Concepts and examples pertaining to combined coding design for efficient codeblock extension are described. A processor of a communication apparatus may combine channel polarization of a communication channel with a first coding scheme for first codeblocks of a smaller size to generate a second coding scheme. The processor may also code second codeblocks of a larger size using the second coding scheme.

Sequence detectors and detection methods are provided for detecting symbol values corresponding to a sequence of input samples obtained from an ISI channel. The sequence detector comprises a branch metric unit (BMU) and a path metric unit (PMU). The BMU, which comprises an initial set of pipeline stages, is adapted to calculate, for each input sample, branch metrics for respective possible transitions between states of a trellis. To calculate these branch metrics, the BMU selects hypothesized input values, each dependent on a possible symbol value for the input sample and L>0 previous symbol values corresponding to possible transitions between states of the trellis. The BMU then calculates differences between the input sample and each hypothesized input value. The BMU compares these differences and selects, as the branch metric for each possible transition, an optimum difference in dependence on a predetermined state in a survivor path through the trellis.

A mobile device includes a display, a mobile-communication modem including a Viterbi decoder (VD) configured to decode a tail biting convolutional code (TBCC)-encoded data, a memory coupled to the mobile-communication modem, and a wireless antenna coupled to the mobile-communication modem and to receive a Physical Downlink Control Channel (PDCCH). The VD is configured to: receive data encoded by TBCC; select a candidate to initiate a training section; determine final path metric (PM) values of possible states at a last step of the training section; determine a PM-related value based on the final PM values of the possible states; and determine an early termination of a decoding for the candidate based on the PM-related value.

Devices, methods and computer programs for accelerating low-density parity-check (LDPC) decoding via scheduling are disclosed. At least some of the example embodiments described herein may allow reducing cost and improving power efficiency beyond that of semiconductor processor scaling currently used in accelerating LDPC decoding.