Abstract: An adaptation technique for decoding low-density parity-check (LDPC) codes for hard disk drive (HDDs) systems is disclosed. The method includes tuning the normalization factor for LDPC decoding for each data zone and read head during the test stage of manufacturing. The LDPC decoder can be either a sum-product algorithm (SPA) decoder or a Min-Sum decoder. The channel detector can be any soft-output detector, such as a soft-output Viterbit detector (SOVA), a BCJR detector, a pattern-dependent noise-predictive (PDNP) detector, or a bi-directional pattern-dependent noise-predictive (BiPDNP) detector. The adaptation technique can optimize the LDPC decoding performance for each data zone and read head, thereby relaxing the acceptance criteria for hard disk drive read/write heads and disk media, enabling acceptance and use of a much broader range of head and media for hard disk drives.

Abstract: This disclosure relates generally to low power data decoding, and more particularly to low power iterative decoders for data encoded with a low-density parity check (LDPC) encoder. Systems and methods are disclosed in which a low-power syndrome check may be performed in the first iteration or part of the first iteration during the process of decoding a LDPC code in an LDPC decoder. Systems and methods are also disclosed in which a control over the precision of messages sent or received and/or a change in the scaling of these messages may be implemented in the LDPC decoder. The low-power techniques described herein may reduce power consumption without a substantial decrease in performance of the applications that make use of LDPC codes or the devices that make use of low-power LDPC decoders.

Abstract: In one embodiment, a method of block decoding is provided. For each of a plurality of data blocks input to a memory arrangement, a plurality of decoding iterations are performed using a circular pipeline of processing stages. For each decoding iteration, one processing stage of the circular pipeline performs a first set and a second set of soft-input-soft-output (SISO) decoding operations on a block of data. The first set of SISO decoding operations produces an intermediate block of data. The second set of SISO decoding operations is performed on the intermediate data block to complete the one decoding iteration. The next decoding iteration of the plurality of decoding iterations is performed using the next processing stage following the one processing stage of the circular pipeline of processing stages.

Abstract: A transmission device transmitting a polarization-multiplexed optical signal includes: a frame encoder configured to encode an electric signal in accordance with a predetermined frame format; an error correction encoder configured to provide encoded signal data as a result of the encoding by the frame encoder with a predetermined error correction code; and a transmission loss information acquiring part configured to acquire transmission loss information based on a loss that the encoded signal data provided with the error correction code incurs when the encoded signal data is transmitted, from a receiving device as a transmission destination. The error correction encoder adjusts a redundancy of the error correction code given to the encoded signal data, based on the transmission loss information acquired by the transmission loss information acquiring part.

Abstract: Apparatus and methods provide relatively low uncorrectable bit error rates, low write amplification, long life, fast and efficient retrieval, and efficient storage density such that a solid-state drive (SSD) can be implemented using relatively inexpensive MLC Flash for an enterprise storage application.

Abstract: A plurality of encrypted packets having common payload data are received, wherein each of the plurality of encrypted packets includes a corresponding parity check field, and wherein a corresponding parity check syndrome for each of the plurality of encrypted packets indicates at least one bit error. A payload portion of each of the plurality of encrypted packets is decrypted to generate a plurality of decrypted payload portions. At least one chase coding technique is used to generate a corrected decrypted payload, based on at least one candidate bit error position and further based on the corresponding parity check syndrome for at least one of the plurality of encrypted packets.

Abstract: In a data processing system having a plurality of error coding function circuitries, a method includes receiving an address which indicates a first storage location for storing a first data value; using a first portion of the address to select one of the plurality of error coding function circuitries as a selected error coding function circuitry; and using the selected error coding function circuitry to generate a first checkbit value, wherein the selected error coding function circuitry uses the first data value to generate the first checkbit value. When the first portion of the address has a first value, a first one of the plurality of error coding function circuitries is selected as the selected error coding function circuitry. When the first portion of the address has a second value, a second one of the plurality of error coding function circuitries is selected as the selected error coding function circuitry.

Abstract: A low-density parity check (LDPC) decoder is provided for decoding low-density parity check (LDPC) encoded data wherein a layer specific attenuation factor is provided for each layer of the LDPC parity check matrix. An attenuation factor matrix comprising a plurality of coefficients specifies the specific attenuation factor for each layer and each iteration of the decoding process. A check node processor performs check node processing for each layer of the parity check matrix associated with the LDPC encoded codeword utilizing the normalized layered min-sum algorithm wherein the attenuation factor of the min-sum algorithm is determined by the coefficients of the attenuation factor matrix.

Abstract: Apparatuses, systems, methods, and computer program products are disclosed for error correcting code (ECC) decoding. A score module is configured to assign a score to a variable node of low density parity check (LDPC) code decoder. The LDPC code decoder may include a plurality of variable nodes associated with a plurality of check nodes. The plurality of variable nodes may correspond to bits of a received code word. The score for the variable node may be based on a count of unsatisfied check nodes associated with the variable node. A variable node update module is configured to update the variable node based on the score. A check node update module is configured to update one or more of the check nodes based on the updated variable node.

Abstract: A computer-implemented method, computer program product, and computing system is provided for managing quality of service for communication sessions. In an implementation, a method may include determining network condition associated with a communication session. The method may also include calculating one or more anticipated performance attributes for each of a plurality of error correction codes based on the network condition. The method may also include determining a quality of experience metric for each of the plurality of error correction codes based on the calculated one or more anticipate performance attributes for each of the plurality of error correction codes. The method may further include establishing one of the plurality of error correction codes for the communication session based on the quality of experience metric for each of the plurality of error correction codes.

Abstract: This disclosure generally relates to encoding, transmission, and decoding of digital video, and more particularly to methods and systems for minimizing decoding delay in distributed video coding (DVC). In one embodiment, a video decoding method is disclosed, comprising: obtaining side information; obtaining a syndrome bit chunk corresponding to a non-key-frame bit-plane; performing, via one or more processors, at least one non-key-frame bit-plane channel decoding iteration using the side information and the syndrome bit chunk; generating a decoded bit-plane via performing the at least one non-key-frame bit-plane channel decoding iteration; determining a bit error rate measure for the decoded bit-plane; determining, based on the bit error rate measure, a number of additional syndrome bit chunks to request; and providing a request for the additional syndrome bit chunks.

Abstract: Systems and methods are provided for decoding data using hard decisions and soft information. In particular, the systems and methods described herein are directed to decoders having variable nodes and check nodes, each with multiple states. The systems and methods include receiving, at a decoder during a first iteration, values for each of a plurality of variable nodes, and determining, during a second iteration, one or more indications for each of a plurality of check nodes based on the one or more values of the variable nodes received during the first iteration. The methods further include updating, at the decoder during the second iteration, the values for each of the variable nodes based on the values of the respective variable node received during the first iteration, and the indications for each of the plurality connected check nodes during the first iteration.

Abstract: A computer-implemented method and computer program product comprising optimal, systematic q-ary codes for correcting all asymmetric and symmetric errors of limited magnitude are provided.

Abstract: A stopping method for an iterative signal processing includes a first step of receiving the state signatures generated by the iterative signal processing. A next step includes accumulating the state signatures into a stopping index variable. A next step includes stopping iterative decoding when the stopping index variable is less than a predetermined threshold.

Abstract: A method for decoding comprises the following steps: receiving a first codeword comprising a plurality of elements of a first finite commutative group and associated to a plurality of symbols in accordance with a first code defining codeword elements by respective summations in said first commutative group; determining, by applying a projection onto elements of the first codeword, a second codeword comprising a plurality of elements of a second finite commutative group having a cardinal strictly smaller than the cardinal of the first finite commutative group, wherein the projection is a morphism from the first finite commutative group to the second finite commutative group; decoding the second codeword in accordance with a second code defining codeword elements by respective summations in said second commutative group.

Abstract: A system providing early termination for channel decoding by re-encoding including a decoding unit, an encoding unit connected to the decoding unit, and a checking unit connected to the decoding unit and to the encoding unit. Via the system, decoded message words produced from the decoding unit are sent back to the encoding unit for re-encoding. Re-encoded words are compared to the decoded codewords by the checking unit and, if they are completely the same, the decoding action of the decoding unit is terminated. The system reduces power consumption and offers a simplified structure, improved decoding throughput, and reduced hardware complexity.

Abstract: A device (20) for an adaptive modulation communication system is provided. The device (20) comprises an input device (21) adapted to receive, from a communication channel, data encoded through a FEC code. A FEC decoder (23) connected downstream of the input device (21) is also provided for FEC decoding the received encoded data and providing error information determined by the FEC decoding. The device according to the invention further comprises means for measuring first error information of the encoded data before FEC decoding the received encoded data, and means for measuring second error information determined by the FEC decoder (23). Means (25) for estimating a condition of the communication channel based on both the first error information and the second error information are also provided.

Abstract: A method and apparatus is disclosed herein for performing wireless communication.

Abstract: A communication system and a method are provided. The communication system includes an encoder configured to encode source data and output an encoded frame including a mother code or a plurality of concatenated daughter codes based on an encoding option. The mother code and the plurality of concatenated daughter codes have a same number of coded data symbols. The mother code includes a first source number of source symbols and a first parity number of parity symbols. The daughter code includes fewer source symbols and fewer parity symbols than the mother code.

Abstract: Methods and apparatus are provided for reading and writing data in q-level cells of solid-state memory, where q>2. Input data is encoded into codewords having N qary symbols, wherein the symbols of each codeword satisfy a single-parity-check condition. Each symbol is written in a respective cell of the solid state memory by setting the cell to a level dependent on the qary value of the symbol. Memory cells are read to obtain read signals corresponding to respective codewords. The codewords corresponding to respective read signals are detected by relating the read signals to a predetermined set of N-symbol vectors of one of which each possible codeword is a permutation.

Abstract: 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.

Abstract: A communication system having a main control portion (MCP) to transmit information destined to a device n cascade levels down, and create an error detection code (CRC code) for data that contains a count of remaining cascade levels until an n-th cascade level and the information. The code is transmitted to an upstream sub-control portion (USCP) with the data. The USCP creates a CRC code for the data, and compares the created and received codes. For a match, the USCP determines whether the information is destined to itself based on the remaining cascade level count. When the information is not so destined, the USCP creates new data with the remaining cascade level count reduced by 1, and a CRC code for the new data, and transmits the created code to a further device, with the new data.

Abstract: Embodiments of apparatus, methods, systems, and devices are described herein for selective error correction in memory with multiple operation modes. In various embodiments, an error correction block (e.g., of a memory controller) may be configured to perform error correction on data read from a first portion of a memory based on a corresponding error correction code read from a second portion of the memory, and to calculate and store the error correction code. A control block coupled to the error correction block may be configured to selectively enable/disable the error correction block to perform the error correction, and to calculate and store the error correction code, based at least in part on a current operation mode of the memory.

Abstract: Methods, systems, and devices are described for forward error correction for flash memory. Encoded data from flash memory may be used to generate a number of data streams. At each of a number of error detection sub-modules operating in parallel, a different one of the data streams is processed. Each error detection sub-module may detect whether a portion of the respective received stream contains an error, and forward the portion to an error correction module. The error correction module, physically separate from the error detection sub-modules, may correct the forwarded portions of the respective received streams containing an error. The age and error rate associated with the flash memory may be monitored, and a coding rate or other aspects may be dynamically adapted to account for these factors.

Abstract: Apparatus and method for processing a physical layer protocol convergence (PLCP) header. In one embodiment, a wireless device includes a PLCP header processor. The PLCP header processor is configured to: process a physical layer header, process a check value based on the physical layer header, and process an error correction code based on the physical layer header and the check value. A concatenation of the physical layer header, check value, and error correction code the PLCP header processor is configured to process consists of a number of information bits that is an integer multiple of a number of information bits per symbol used to encode the PLCP header.

Abstract: The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for performing data decoding.

Abstract: Aspects of the disclosure can provide a method and an apparatus to decode a data stream based on multiple transmissions with efficient usages of storage and power resources. The method can include receiving a first plurality of encoded code blocks corresponding to a first transmission of a transport block, decoding the first plurality of encoded code blocks into decoded code blocks, error detecting the decoded code blocks, and storing a decoding history of the decoded code blocks. Further, the method can include receiving a second plurality of encoded code blocks corresponding to a retransmission of the transport block. The second plurality of encoded code blocks can map the first plurality of encoded code blocks, respectively. The method can selectively decode a subset of the second plurality of encoded code blocks based on the decoding history. In addition, the method can include storing soft bits for code blocks that failed decoding.

Abstract: An encoder module includes P/L parity shift registers that are sequentially coupled, wherein an input of a first parity shift register of the parity shift registers is coupled to the input of the encoder module, an output of the last parity shift register of the parity shift registers is coupled to the output of the encoder module, each of the parity shift registers being configured to store L parity digits. The encoder module also includes a feedback circuit comprising P/L parity generation modules, wherein each of the parity generation modules is coupled to an output of a corresponding one of the parity shift registers by a switch and also coupled to the input of the first parity shift register, wherein each of the parity generation modules is configured to generate L parity digits for transmission to the input of the first parity shift register when its corresponding switch is closed.

Abstract: Implementations include systems, methods and/or devices suitable for use in a memory system that may enhance the performance of error control codes used to improve the reliability with which data can be stored and read. Some implementations include systems, methods and/or devices enabled to generate and utilize soft information for decoding encoded data read from a storage medium. More specifically, some implementations utilize a collection of characterization vectors that include soft information values for bit-tuples that may be read from the storage medium for various combinations of the storage medium characterization parameter values. Some implementations are enabled to determine and utilize read comparison signal values associated with one or more storage medium characterization parameter values.

Abstract: Methods and apparatuses are provided for decoding a codeword using an iterative decoder. The iterative decoder, in a first decoding mode, performs a number of channel iterations on the codeword, determines a first syndrome weight after a first time period, and determines a second syndrome weight after a second time period. Each channel iteration includes an iteration of the channel detector and at least one iteration of the inner iterative decoder. The iterative decoder, in a second decoding mode, determines a true syndrome of the codeword, and processes the codeword based on the true syndrome of the codeword. The codeword is processed using the second decoding mode in response to determining that the first and second determined syndrome weights are less than a syndrome weight threshold.

Abstract: System and methods for storing data encoded with error information in a storage medium are provided. A binary data and an encoded binary error signals are received. The encoded binary error signal includes information that represents occurrence of errors in the binary data signal. The binary data and encoded binary error signals are encoded to generate a binary codeword signal. Bits of the binary codeword signal that represent coding information and the binary data signal are extracted. The extracted bits of the binary codeword signal are stored in a first storage medium. The binary packed data signal is retrieved from the first storage device and decoded to recover the binary data signal and a syndrome. Error information corresponding to the encoded binary error signal may be determined based on the syndrome.

Abstract: A method is disclosed for correcting bit errors in a block-coded data frame. The method includes receiving a plurality of block-coded symbols, each symbol including at least one unencoded bit; detecting a bit error in one of the plurality of symbols associated with the unencoded bits, the detecting carried out in accordance with an error detection algorithm; identifying the symbol having the bit error from among the plurality of symbols based on the error detection algorithm; and correcting the bit error in the identified symbol.

Abstract: Methods and apparatus are provided for improved iterative error-erasure decoding. A signal is decoded by obtaining a plurality of symbols associated with the signal and one or more corresponding reliability values; generating at least one erasure list comprised of L symbols and at least one shortened erasure list comprised of L? symbols, where L? is less than L; and constructing an erasure set by taking erasures from at least one of the erasure list and the shortened erasure list. A signal is also processed by generating one or more reliability values using a soft-output detector; generating an erasure list of symbols by comparing the reliability values to at least one reliability threshold value (or by sorting); and performing error erasure decoding using the erasure list. The size of the erasure list can optionally be adjusted using feedback information.

Abstract: According to one embodiment, a memory system includes a non-volatile semiconductor memory that includes memory cells each storing 3 bits, a control unit that writes data to the non-volatile semiconductor memory, and an encoding unit that generates a first parity for user data stored in the first page, a second parity for user data stored in the second page, and a third parity for user data stored in the third page. The user data, the first parity, the third parity, and a portion of the second parity are written to the non-volatile semiconductor memory by a first data coding and a portion of the second parity and a portion of the third parity are written to the non-volatile semiconductor memory by second data coding in which the first page is 0 bit, the second page is 2 bits, and the third page is 1 bit.

Abstract: A method and system to improve the performance and/or reliability of a solid-state drive (SSD). In one embodiment of the invention, the SSD has logic to compress a block of data to be stored in the SSD. If it is not possible to compress the block of data below the threshold, the SSD stores the block of data without any compression. If it is possible to compress the block of data below the threshold, the SSD compresses the block of data and stores the compressed data in the SSD. In one embodiment of the invention, the SSD has logic to dynamically adjust or select the strength of the error correcting code of the data that is stored in the SSD. In another embodiment of the invention, the SSD has logic to provide intra-page XOR protection of the data in the page.

Abstract: A decoding method for low density parity check (LDPC) and an electric device using the decoding method are provided. The decoding method includes: receiving a message and executing an iteration decoding to the message; obtaining first belief values of the message in an (i?1)th iteration; obtaining a first energy summation of the first belief values; obtaining second belief values of the message in an ith iteration; obtaining a second energy summation of the second belief values; determining whether the second energy summation is smaller than the first energy summation and whether a difference between the first energy summation and the second energy summation is larger than a first threshold; if yes, generating a decoding result according to the first belief values. Therefore, a bit error rate of the decoding is decreased.

Abstract: A memory system includes a link having at least one signal line and a controller. The controller includes at least one transmitter coupled to the link to transmit first data, and a first error protection generator coupled to the transmitter. The first error protection generator dynamically adds an error detection code to at least a portion of the first data. At least one receiver is coupled to the link to receive second data. A first error detection logic determines if the second data received by the controller contains at least one error and, if an error is detected, asserts a first error condition. The system includes a memory device having at least one memory device transmitter coupled to the link to transmit the second data. A second error protection generator coupled to the memory device transmitter dynamically adds an error detection code to at least a portion of the second data.

Abstract: Provided is a wireless communication system employing network coding which can set transmission quality for each destination of packets and improve throughput. The wireless communication system is provided with a wireless relay station apparatus and wireless terminal station apparatuses. The wireless relay station apparatus selects coding rates to be used for a first packet and a second packet in accordance with communication quality required for the first packet and the second packet, generates error correction encoded packets having the same data length from the first packet and the second packet using the selected coding rates, performs network encoding on the error correction encoded first and second packets to generate a network encoded packet, and transmits the generated network encoded packet.

Abstract: A storage system includes a channel detector, an LDPC decoder, and an erasure block. The channel detector is configured to receive data corresponding to data read from a storage and output an LLR signal. The LDPC decoder is configured to receive the LLR signal and output a feedback signal to the channel detector. The erasure block is configured to erase at a portion of at least one of the LLR signal and the feedback signal. A method for testing includes generating an error rate function corresponding to an erasure pattern. The function is a function of a number of LDPC iterations. The method includes determining testing parameters at least in part based on the error rate function, wherein the testing parameters comprise a testing number of LDPC iterations, a passing error rate, and the erasure pattern. The method includes testing storage devices using the testing parameters.

Abstract: A method includes, in a decoder of an Error Correction Code (ECC), maintaining only aggregated information regarding a set of messages, a function of which is to be reported from a first node to a second node of the decoder. The function of the set is determined and reported using the aggregated information. After reporting the function, one of the messages in the set is replaced with a new message. The aggregated information is updated to reflect the set having the new message, and the function of the set having the new message is determined and reported using the updated aggregated information.

Abstract: Error correction coding for streaming communication is provided. A streaming problem is modeled as a non-multicast network problem with a nested receiver structure. Each packet in the streaming problem corresponds to a link, and each deadline in the streaming problem corresponds to a receiver in the non-multicast network problem. For the non-multicast network problem, content to be transmitted in multiple packets to multiple receivers is obtained. Each of the receivers is required to decode specific independent messages from the content, at given time steps, and has access to a subset of the content received by another receiver. The content is allocated into multiple packets to be transmitted on multiple links. No coding occurs across information demanded by different receivers. A capacity region defines a set of information rate vectors that can be communicated to the receivers successfully. A rate vector is successfully communicated if it complies with various inequalities.

Abstract: In a method of encoding data, a data block is received; transformed, error-corrected encoded data blocks based on the received data block are generated and one is selected based on a constraint; and the selected data block is transmitted. The method may include adding, to the received data block, pivot data corresponding to different transformations. In an apparatus, an encoded data generator is configured to generate different encoded data block candidates based on a received data block, and a selector is configured to select one of the candidates to output as encoded data based on a constraint. The encoded data generator may include a transformer configured to apply one or more transformations to the received data block, and an error correction code (ECC) encoder configured to apply error correction to the received data block. The encoded data generator and the selector may be included in a transmitter.

Abstract: The invention is a memory system having two memory banks which can store and recall with memory error detection and correction on data of two different sizes. For writing separate parity generators form parity bits for respective memory banks. For reading separate parity detector/generators operate on data of separate memory banks.

Abstract: A first set of one or more soft detector outputs is generated. It is determined if error correction decoding is successful using the first set of soft detector outputs. In the event it is determined error correction decoding is not successful, a second set of one or more soft detector outputs is generated where a largest likelihood associated with the first set is greater than a largest likelihood associated with the second set.

Abstract: Rate control adaptable communications. A common trellis is employed at both ends of a communication system (in an encoder and decoder) to code and decode data at different rates. The encoding employs a single encoder whose output bits may be selectively punctured to support multiple modulations (constellations and mappings) according to a rate control sequence. A single decoder is operable to decode each of the various rates at which the data is encoded by the encoder. The rate control sequence may include a number of rate controls arranged in a period that is repeated during encoding and decoding. Either one or both of the encoder and decoder may adaptively select a new rate control sequence based on a variety of operational parameters including operating conditions of the communication system, a change in signal to noise ratio (SNR), etc.

Abstract: Data is processed by selecting one or more bits in a codeword to replace with an erasure. The selected bits in the codeword are replaced with the erasure and error correction decoding is performed on the codeword with the erasure in place for the selected bits.

Abstract: Low-Density Parity-Check (LDPC) codes offer error correction at rates approaching the link channel capacity and reliable and efficient information transfer over bandwidth or return-channel constrained links with data-corrupting noise present. LDPC codes also offer error correction performance approaching channel capacity exponentially fast in terms of the code length, linear processing complexity, and parallelism that scales with the code length. They also offer challenges relating to the decoding complexity of the binary error-correction codes themselves and error floors limiting achievable bit-error rates. A new Relaxed Half-Stochastic (RHS) decoding algorithm is presented that reduces decoding complexity for high decoding throughput applications. The RHS algorithm uses an approach based on stochastic decoding algorithms but differs significantly from the conventional approaches of LDPC decoder implementation.

Abstract: A method for implementing adaptive error correction in a memory, comprising the steps of (A) decoding a page of data read from a memory, (B) selecting one of a plurality of histograms based on a measured code word error rate of the decoded page and (C) applying an error correction code rate based on the selected histogram. The error correction code rate allows the memory to use a minimum number of error correction bits to provide reliable operation of the memory.

Abstract: A data storage device may comprise an array of flash memory devices and a controller coupled thereto, configured to program and read data from the array responsive to received data access commands. The array may comprise a plurality of blocks, each comprising a plurality of flash pages (F-Pages), each of which comprising an integer number of one or more error correcting code pages (E-Pages), at least some of which comprising a data portion and an error correction code (ECC) portion. The controller may be configured to store a plurality of logical pages (L-Pages) in one or more of the plurality of E-Pages, at least some being unaligned with boundaries of the E-Pages; and to adjust, in at least one of the blocks, the size of the ECC portion and correspondingly adjust the size of the data portion of the E-Pages.

Abstract: A communication device includes a turbo encoding section including a plurality of component encoders, wherein the plurality of component encoders within the turbo encoding section use different constraint lengths.