1415results about "Error correction/detection using linear codes" patented technology

Embodiments are directed to transmitting L1 pre-signaling information with predetermined modulation and code rate such that L1 pre-signaling information can be received without preliminary knowledge on the network. L1 pre-signaling information makes it possible to receive the L1 signaling information, data link layer information, and notification data that may have configurable code rates and modulation. Therefore, L1 pre-signaling information can be thought of as signaling metadata (i.e., information about other signaling information). L1 signaling is divided into pre-signaling and signaling parts. The pre-signaling part includes parameters used for receiving the L1 signaling information. L1 pre-signaling signaling enables the receiver to receive the signaling itself (L1 signaling and data link layer information) by informing the receiver about the type of modulation, coding, and the like, used to transmit the L1 signaling, data link layer, and notification information.

Coding within noisy communications channels is essential but a theoretical maximum rate defines the rate at which information can be reliably transmitted on this noisy channel. Capacity-achieving codes with an explicit construction eluded researchers until polar codes were proposed. However, whilst asymptotically reaching channel capacity these require increasing code lengths, and hence increasingly complex hardware implementations. It would be beneficial to address architectures and decoding processes to reduce polar code decoder complexity both in terms of the number of processing elements required, but also the number of memory elements and the number of steps required to decode a codeword. Beneficially architectures and design methodologies established by the inventors address such issues whilst reducing overall complexity as well as providing methodologies for adjusting decoder design based upon requirements including, but not limited to, cost (e.g. through die area) and speed (e.g. through latency, number of cycles, number of elements etc).

A random code length polar encoding method includes: during construction of a polar code, if the code length is not the power of 2, using a group of virtual channels with the capacity of zero for supplementing the channel number to be the power of 2; performing mixed mapping for each channel according to the capacity equalization principle; and performing polar conversion for the obtained channels, selecting the channels with higher capacity from converted channels according to the designed bitrate for transmitting information bit sequences, and using the rest channels for transmitting a known fixed bit sequence of a receiving end and a transmitting end. The method enables polar encoding to allow the code length to be an optional positive integer and is applicable to multi-carrier and high-order modulation systems, and the added perforating operation enables the encoding bit sequences outputted by an encoder to be optional in length; by means of channel mixed mapping, polar encoding can adapt to different component channels of parallel channels, so that anti-noise performance is good; and flexibility of using polar codes for a practical digital communication system is greatly improved, and accordingly the method has good application prospect.

The invention discloses a hybrid automatic repeat request transmission method based on a polarization code. The hybrid automatic repeat request transmission method based on the polarization code comprises the following steps: after a coding bit sequence obtained after polarization coding is carried out to a sent information bit sequence is punched via a sending end, sending into a channel to be transmitted; decoding a received signal by a receiving end for CRC (cyclic redundancy check); if the received signal passes the check, feeding back an ACK (acknowledgement character) signal to the sending end, and otherwise, sending a NACK (negative acknowledgement) signal; if the sending end receives the NACK signal, sending one part of uncoded information bits to a receiving end again; according to the coding bit received for the first time and a newly-received information bit, decoding again by the receiving end; if a decoding result still does not pass the CRC, sending the other part of uncoded information bits to the receiving end again by the sending end; according to the coding bit received for the first time, the information bit received in the previous time and the newly-received information bit, decoding again by the receiving end; continuously executing the process; and finishing one whole transmission process until the sending end receives the ACK signal or the number of sending times reaches a preset maximum value.

A method of decoding data encoded with a polar code and devices that encode data with a polar code. A received word of polar encoded data is decoded following several distinct decoding paths to generate a list of codeword candidates. The decoding paths are successively duplicated and selectively pruned to generate a list of potential decoding paths. A single decoding path among the list of potential decoding paths is selected as the output and a single candidate codeword is thereby identified. In another preferred embodiment, the polar encoded data includes redundancy values in its unfrozen bits. The redundancy values aid the selection of the single decoding path. A preferred device of the invention is a cellular network device, (e.g., a handset) that conducts decoding in accordance with the methods of the invention.

The invention belongs to the field of channel encoding, and particularly relates to a polar code coding and decoding method with segmented cyclic redundancy check (Cyclic Redundancy Check, CRC) auxiliary check. According to the polar code coding and decoding method provided by the invention, certain information bits are sacrificed to check polar codes to improve the decoding performance, and assuming that the length of used CRC is K-k bits, the information is averagely divided into M segments by segmented CRC check, k / M bits of information and (K-k) / M bits of CRC check information constitute an information structure of each segment, as shown in Fig.2. The information bits are encoded and transmitted by a channel, finally, SCL decoding and check are carried out on the information received by a receiving end, and L maximum storage paths are available. The polar code coding and decoding method provided by the invention can be used for shortening the time delay, bringing great convenience for real-time communication, saving the memory space of a register and providing great convenience for hardware realization.

The invention discloses a density evolution based polarization code constructing method and polarization code coding and decoding system. According to the invention, the code length N and the information bit length K of an information code to be processed are obtained, an expectation value set of a log-likelihood ratio probability density function of N bit channels, K bit channels are selected as the information bit channels according to the expectation value set and information bit information index vector quantity is generated; an information bit sequence and a fixed bit sequence are mixed and the mixed bit vector quantity is multiplied by a polarization code for generating a matrix so as to output an encoding sequence; the encoding sequence is modulated and input into a transmission channel and the sequence output by the transmission channel is subjected to decoding operation by adopting a polarization code decoding algorithm, bit error probability and frame error rate of the decoded code are calculated and a design signal to noise ratio is changed, the above operation is repeated until the bit error probability and frame error rate become the minimum. The method and system provided by the invention are suitable for general binary system memoryless channels, the bit error probability and frame error rate are low, the calculation complexity is low and the communication performance of a communication system is improved.

The invention discloses a channel-polarization-based encoder for a staggered structure duplication code, and an encoding method and decoding methods thereof. The encoder consists of a duplication bit buffer with a storage capacity of L bits, a bit position mapper with a length N and a channel polarization device with the length N which are connected in sequence. The encoding method based on the encoder comprises the following steps of: embedding duplicated encoding into a channel polarization process, and introducing a duplicated relationship between parts of the bits of code blocks transmitted in sequence during the channel polarization for encoding. In addition, the invention further provides two decoding methods, which comprise the following steps of: decoding by using a simple and rapid successive cancellation (SC) algorithm, and performing iterative decoding by using a Tanner-graph-based belief propagation algorithm with excellent performance. On the basis of the innovative structure encoder, the encoding and decoding methods provided by the invention are stronger in error correction capability under the condition of not increasing the decoding complexity, and the transmission performance is obviously improved. The encoding and decoding methods are particularly applicable to an actual communication engineering system and have a good popularization and application prospect.

A data storage system configured to adaptively code data is disclosed. In one embodiment, a data storage system controller determines a common memory page size, such as an E-page size, for a non-volatile memory array. Based on the common memory page size, the controller selects a low-density parity-check (LDPC) code word length from a plurality of pre-defined LDPC code word lengths. The controller determines LDPC coding parameters for coding data written to or read from the memory array based on the selected LDPC code word length. By using the plurality of pre-defined LDPC code word lengths, the data storage system can support multiple non-volatile memory page formats, including memory page formats in which the common memory page size does not equal any LDPC code word length of the plurality of pre-defined LDPC code word lengths. Flexibility and efficiency of data coding can thereby be achieved.

The invention discloses a coder based on repeated coding and channel polarization and a coding / decoding method thereof. The coder comprises two coding modules with the same structure; each coding module is provided with a repeated coder group, a bit position mapper with the length of N and a channel polarization device with the length of N, wherein the repeated coder group has m*L output ports and is composed of L sequentially-arranged repeated coders with the repeating times of m; and the two coding modules are connected together through a coding mode selector between the repeated coder and the bit position mapper. The invention provides a concrete method of embedding repeated codes in the channel polarization process to perform channel coding and decoding based on the coder; and compared with the polarization code of the limited length in the prior art, the coding / decoding method disclosed by the invention has stronger error correction capability and obviously improves the transmission performance on the premise of rarely increasing the decoding complexity, is particularly suitable for the practical engineering systems of mobile communication, satellite communication, underwatercommunication and the like, and has good popularization and application prospects.

The invention relates to a polarization code decoding method for cyclic redundancy check assistance. When a polarization code is decoded, in all the routes with cyclic redundancy check values of corresponding bit estimation sequences of being zero from a root node to leaf nodes on a code tree corresponding to the polarization code, one route with maximum reliability metric value is searched by taking a list or stack as assistance for route search, and the bit estimation sequence corresponding to the route is output as a decoding result. The method comprises the following operation steps of: determining parameters according to a search assistance method, constructing an auxiliary structure of the decoding method, searching a candidate bit estimation sequence and executing cyclic redundancy check. By adopting the method disclosed by the invention, error correcting capability of a communication system which adopts the polarization code as channel coding is greatly improved, operation steps are simpler, and operation complexity is equivalent to or even lower than that of a Turbo code coding and decoding method used in a WCDMA (wideband code division multiple access) system, thus the method disclosed by the invention has a good practical prospect.

To increase the robustness of a broadcast DTV signal, complete (207, 187) Reed-Solomon forward-error-correction codewords are coded using binary linear block codes that reduce code rate by two or slightly less, enabling a DTV receiver to correct bit errors. Also, a DTV receiver can use a (15, 8), (16, 8) or (8, 4) block code to locate erroneous bytes for decoding (207, 187) Reed-Solomon code, so twice as many erroneous bytes can be corrected in a 187-byte data packet. The reduced code rate permits robust transmission of a 187-byte data packet in only two data segments and its super-robust transmission using a restricted symbol alphabet in only four data segments. This simplifies time-division multiplexing of data segments used for ordinary 8VSB transmissions with those used for robust and super-robust transmissions. Procedures to make legacy DTV receivers disregard data segments used for robust and super-robust transmission are disclosed.

A method, apparatus, and chipset are provided for constructing hybrid automatic repeat request (HARQ) rate-compatible polar codes for communication channels. The method includes constructing, in a terminal, a base polar code of length 2n; and determining a sequence of m<2n bits to puncture in the base polar code by testing a predetermined criterion at most (22n+2n) / 2−1 times.

Methods and apparatus of the present invention can be used to implement a communications system wherein different devices using the same LDPC code can be implemented using different levels of parallelism. The use of a novel class of LDPC codes makes such differences in parallelism possible. Use of a factorable permuter in various embodiments of the invention make LDPC devices with different levels of parallelism in the encoder and decoder relatively easy to implement when using the codes in the class of LDPC codes discussed herein. The factorable permuter may be implemented as a controllable multi-stage switching devices which performs none, one, or multiple sequential reordering operations on a Z element vector passed between memory and a Z element vector processor, with the switching one individual vectors being controlled in accordance with the graph structure of the code being implemented.

The invention provides a decoding method and a decoding device for polar codes concatenated with a cyclic redundancy check (CRC). The decoding method includes the following steps: SC-list decoding is carried out on the polar codes according to the number, which is L, of survival paths to obtain the L survival paths, wherein the L is a positive integer; each of the L survival paths is subjected to the CRC; and when none of the L survival paths passes the CRC, the number of the survival paths is increased, and decoding results of the polar codes are obtained according to the number, which is increased, of the survival paths. According to the decoding method and the decoding device for the polar codes concatenated with the CRC, the path number of the survival paths is adjusted according to the result of the CRC, and therefore the paths which can pass the CRC can be output as far as possible, and the decoding performance is improved.

An apparatus, system, and method are disclosed to increase data integrity in a redundant storage system. The receive module receives a read request to read data from a logical page spanning an array of N+P number of storage elements. The array of storage elements includes N number of the storage elements each storing a portion of an ECC chunk and P number of the storage elements storing parity data. The data read module reads data from at least a portion of a physical page on each of X number of storage elements of the N+P number of storage elements where X equals N. The regeneration module regenerates missing data. The ECC module determines if the read data and any regenerated missing data includes an error. The read data combined with any regenerated missing data includes the ECC chunk.

A systematic encoder such as a systematic polar encoder for channel encoding to ameliorate the effects of noise in a transmission channel. The codeword carries a data word to be transmitted transparently, and also carries a parity part derived from the data word and a fixed word. Implementations advantageously reduce coding complexity to the order of N log(N), wherein N is the dimension of a matrix of the nth Kronecker power associated with a matrix effectively employed by the encoder.

The embodiment of the invention provides an HARQ (Hybrid Automatic Repeat Request) signal transmitting method and device and receiving method and device based on polar codes. When transmitting is carried out at a time, when it is judged that there are surplus data blocks, one data block is selected out from the surplus data blocks as an initial transmitting information sequence; the combination of first sub-sequences and second sub-sequences corresponding to negative acknowledge signals in a first retransmitting control queue is determined as a retransmitting information sequence, wherein the first sub-sequences and the second sub-sequences are stored in a transmitting cache queue; the initial transmitting information sequence and the retransmitting information sequence are determined as to-be-transmitted information sequences; one first sub-sequence of the determined to-be-transmitted information sequences is stored in the transmitting cache sequence; polar coding is carried out to the to-be-transmitted information sequences; and the to-be-transmitted information sequences are transmitted. The accurate decoding probability of the information sequences failed to be transmitted for former M times is improved; therefore, the throughput of the communication system is improved; the average transmitting and receiving times before the accurate decoding is carried out to the to-be-transmitted information sequences is reduced; and therefore, the transmission delay of the communication is reduced.

The invention discloses a polarization code and multi-bit even parity check code cascaded error correction coding method. The method comprises the steps: a transmitting end encoder utilizes a multi-bit even parity check code as an outer code, and utilizes a polarization code as an inner code; a receiving end decoder decodes by utilizing a modified successive cancellation list (SCL) decoding algorithm. On the aspect of error correction performance, comparing with the prior art utilizing middle-short code length non-cascaded polarization codes of the SCL decoding algorithm, the polarization code and multi-bit even parity check code cascaded error correction coding method has the advantages that frame error rate performance of a system can be remarkably improved, and a maximum likelihood bound (ML Bound), which cannot be broken through by the SCL decoding algorithm, can be remarkably broken through. On the aspect of engineering realization, according to the polarization code and multi-bit even parity check code cascaded error correction coding method, the outer code utilizes the multi-bit even parity check code, which is simple to code; the modified SCL decoding algorithm is utilized to decode, bit decision and even parity check are combined to be carried out in a decoding process, and compared with the original SCL decoding algorithm, the method provided by the invention does not increase the decoding complexity, and facilitates the engineering realization.

An apparatus and method for interleaving and puncturing are provided. The apparatus includes: an interleaver formed of a plurality of columns and rows, configured to perform interleaving by writing bits input to the interleaver in the plurality of columns and reading the bits from each row of the plurality of columns in which the bits are written; and a puncturer configured to puncture a predetermined number of bits among the bits read from the interleaver.

A method and apparatus for providing a secure transmission based on a polar code are provided. A device generates an output bit sequence by applying a polar code generator matrix to an input bit sequence and transmits the output bit sequence to a target receiver. The input bit sequence includes first information bits, second information bits and third information bits. The first information bits correspond to gray bit channels for the target receiver and bad bit channels for an eavesdropper. The third information bits correspond to good bit channels for the target receiver and gray bit channels for the eavesdropper.

The embodiments of the invention provide a data processing method and apparatus. The method comprises: performing code block segment processing on a data block so as to obtain multiple first processing blocks, the difference of the bit numbers of any two of the multiple first processing blocks being not greater than one bit; according to a filling bit and the multiple first processing blocks, determining multiple second processing blocks, the value of the filling bit being a preset value; adding continuous N-K fixation bits for each of the multiple second processing blocks so as to obtain multiple third processing blocks, the values of the fixation bits being preset values, and (N-K)>=0; and according to the multiple third processing blocks, performing polar coding. In the embodiments of the invention, the data blocks are segmented as uniformly as possible and are subjected to filling bit processing and fixation bit processing so as to perform the polar coding and reduce performance differences among code blocks.

The invention discloses a polarization decoding method based on subsection CRC and belongs to the technical field of wireless communication channel coding. The subsection CRC (cyclic redundancy check) is utilized to improve an existing list successive elimination polarization decoding algorithm, and subsection polarization code CRC is carried out on an original information sequence at a coding end; and at a decoding end, the whole list successive elimination and decoding process is enabled to be divided into a plurality of subsections, CRC is carried out in each subsection, and unsuccessful decoding is judged according to the CRC check result or screening of ineffective paths is carried out. The subsection CRC and the list successive elimination polarization decoding algorithm are combined, so that time complexity of polarization decoding can be effectively reduced, and especially in the low SNR (signal to noise ratio) region, the time complexity of decoding is reduced obviously.

A multiple access scheme is described. One or more encoders are configured to encode a plurality of bit streams using Low Density Parity Check (LDPC) coding. The bit streams correspond to a respective plurality of terminals. The plurality of bit streams are converted to provide a multiple access scheme for the terminals.

A systematic distributed storage system (DSS) comprising: a plurality of storage nodes, wherein each storage node configures to store a plurality of sub blocks of a data file and a plurality of coded blocks, a set of repair pairs for each of the storage nodes, wherein the system is configured to use the respective repair pair of storage nodes to repair a lost or damaged sub block or coded block on a given storage node. Also a distributed storage system DSS comprising h non-empty nodes, and data stored non homogenously across the non-empty nodes according to the storing codes (n,k). Further a method for determining linear erasure codes with local repairability comprising: selecting two or more coding parameters including r and δ; determining if an optimal [n, k, d] code having all-symbol (r, δ)-locality (“(r, δ)a”) exists for the selected r, δ; and if the optimal (r, δ)a code exists performing a local repairable code using the optimal (r, δ)a code.

The invention discloses a method and device for rate matching of Polar codes. The method comprises the steps of: performing Polar code encoding on an information bit sequence with a K-bit length, and generating an encoding bit sequence with an M-bit length; selecting Nmin bits from the encoding bit sequence as the first bit to Nmin-th bit of a bit sequence to be transmitted during a hybrid automatic repeat request (HARQ) process; and determining each bit of (Nmin+1)th bit to Nmax-th bit of the bit sequence to be transmitted from the information bit sequence and the encoding bit sequence, wherein each bit of the (Nmin+1)th bit to the Nmax-th bit of the bit sequence to be transmitted is determined according to a frame error rate of the bit sequence to be transmitted when each bit is added into the bit sequence to be transmitted. By adopting the method of the embodiment of the invention, HARQ transmission based on Polar code encoding can be achieved, and better encoding gain can be obtained.

Integrated circuit memory devices include a memory cell array having therein a plurality of stored data bits and a plurality of parity bits generated from a plurality of write data bits received by the memory device during a write operation. The plurality of stored data bits and the plurality of parity bits may collectively form a word having a length of m+p bits, where m and p are integers. An error check circuit is provided that converts the plurality of stored data bits and the plurality of parity bits into a plurality of syndrome bits (e.g., Si) that designate a location of a bit error in the plurality of stored data bits when compared against the original write data bits. An error correction circuit is provided that uses the plurality of syndrome bits to correct an error in the plurality of stored data bits and generate a plurality of read data bits that match the plurality of original write data bits.

Embodiments of the present invention provide a decoding method and a decoding apparatus for a polar code. The method comprises: grouping a first polar code having a length of N into s second polar codes, a length of each second polar code being N / s, N and s being integer powers of 2, and N>s; performing path splitting of list decoding on s second polar codes concurrently, and combining split paths of s second polar codes after path splitting, so as to obtain multiple combined paths having a length of N; choosing a first combined path from multiple combined paths having a length of N bits, the first combined path being a path having the greatest path metric value among the multiple combined paths having a length of N bits, or a path passing cyclic redundancy check (CRC) among the multiple combined paths having a length of N bits; and obtaining a decoding result of the first polar code according to the first combined path. In this case, a decoding throughput of the polar code can be improved, and a decoding delay can be decreased.

An apparatus or method for minimizing the total accessing cost, such as minimizing repair bandwidth, delay or the number of hops including the steps of minimizing the number of nodes to be engaged for the recovery process using a polynomial-time solution that determines the optimal number of participating nodes and the optimal set of nodes to be engaged for recovering lost data, where in a distributed database storage system, for example a dynamic system, where the accessing cost or even the number of available nodes are subject to change results in different values for the optimal number of participating nodes. An MDS code is included which can be reused when the number of participating nodes varies without having to change the entire code structure and the content of the nodes.