摘要:
Systems and methods are provided for implementing error identification and evaluation for a Reed-Solomon (RS) error-correction code (ECC) system. The BMA algorithm and/or list decoding may produce one or more error locator polynomials that are related to a decision-codeword. An accelerated Chien search can be used to more quickly evaluate the one or more error locator polynomial. If the accelerated Chien search identifies a valid error locator polynomial, a normal Chien search can be used to identify error locations, and Forney's algorithm or an equivalent technique can be used to evaluate the error values. A RS ECC decoder can include a computation circuit that evaluates an error locator polynomial or an error evaluator polynomial. The computation circuit can include computation components that receive the coefficients of the polynomials.
摘要:
Systems and methods are provided for implementing list decoding in a Reed-Solomon (RS) error-correction system. A detector can provide a decision-codeword from a channel and can also provide soft-information for the decision-codeword. The soft-information can be organized into an order of combinations of error events for list decoding. An RS decoder can employ a list decoder that uses a pipelined list decoder architecture. The list decoder can include one or more syndrome modification circuits that can compute syndromes in parallel. A long division circuit can include multiple units that operate to compute multiple quotient polynomial coefficients in parallel. The list decoder can employ iterative decoding and a validity test to generate error indicators. The iterative decoding and validity test can use the lower syndromes.
摘要:
Systems and methods are provided for implementing list decoding in a Reed-Solomon (RS) error-correction system. A detector can provide a decision-codeword from a channel and can also provide soft-information for the decision-codeword. The soft-information can be organized into an order of combinations of error events for list decoding. An RS decoder can employ a list decoder that uses a pipelined list decoder architecture. The list decoder can include one or more syndrome modification circuits that can compute syndromes in parallel. A long division circuit can include multiple units that operate to compute multiple quotient polynomial coefficients in parallel. The list decoder can employ iterative decoding and a validity test to generate error indicators. The iterative decoding and validity test can use the lower syndromes.
摘要:
A decoder for decoding low-density parity-check codes comprises a first calculator to calculate LLrRml, for each parity check equation, at iteration i−1. A detector detects LLrRml, at iteration i, in response to the first calculator. A second calculator calculates LLrQLm, for each parity check equation, at iteration i in response to the detector. LLrQLm represents information from bit node l to equation node m, one for each connection. LLrRml represents information from equation node m to bit node l, one for each connection. The first calculator is responsive to the second calculator.
摘要:
Systems and methods for constructing concatenated codes for data storage channels, such as holographic storage channels, are provided. The concatenated codes include an outer BCH code and an inner iteratively decodable code, such as an LDPC code or turbo code. The correction power and coding rate of one or both of the codes may be programmable based on the channel characteristics and the desired SNR coding gain. The correction power and/or coding rate of the inner and/or outer code may also be dynamically adjusted in real-time to compensate for time-varying error conditions on the channel.
摘要:
The present invention directed to a method and apparatus to perform low-density parity-check code encoding of user data u of length Nu, by inserting parity data p of length Np into output data c of length N in accordance with a parity matrix H such that H·c=0, comprising the steps of: (a) receiving the user data of block length Nu; (b) decomposing H·c into a first component Hu·u corresponding to the user data and a second component Hp·p corresponding to the parity data such that Hu·u+Hp·p=0; (c) calculating a vector u=Hu·u; and (d) calculating p=Hp−1·u.
摘要翻译:本发明涉及一种方法和装置,通过插入长度为N
的奇偶校验数据p来执行长度为N 的用户数据u的低密度奇偶校验码编码 >根据奇偶校验矩阵H使得Hc = 0,包括以下步骤:(a)接收块长度N N的用户数据; (b)将Hc分解成与用户数据相对应的第一分量H ut uu和对应于奇偶校验数据的第二分量H P p P,使得H u sub> .u + H
摘要:
A data transmission system is provided for transmitting user data to and receiving data from a communication channel, including a parity check matrix having M tiers, wherein M≦2, Dmin=2*M for M=1 . . . 3 or 2*M≦Dmin≦6 for M>3, wherein Dmin is the minimum Hamming distance, tc=M, wherein tc is the column weight, and cycle−4=0. A linear block encoder encodes the user data in response to the parity check matrix, and a transmitter transmits an output of the linear block encoder to the communication channel. A soft channel decoder decodes data, and a soft linear block code decoder to decode data decoded by the soft channel decoder in response to the parity check matrix.
摘要:
An ERSEC system that applies a level of error correction that is inversely related to susceptibility to error as indicated by a signal-to-noise ratio (SNR) profile of a channel. The SNR profile is estimated, detected or retrieved from an external source. The ERSEC system is used with any channel for which the SNRs can vary spatially, temporally or both.
摘要:
Systems and methods are provided for implementing list decoding in a Reed-Solomon (RS) error-correction system. A detector can provide a decision-codeword from a channel and can also provide soft-information for the decision-codeword. The soft-information can be organized into an order of combinations of error events for list decoding. An RS decoder can employ a list decoder that uses a pipelined list decoder architecture. The list decoder can include one or more syndrome modification circuits that can compute syndromes in parallel. A long division circuit can include multiple units that operate to compute multiple quotient polynomial coefficients in parallel. The list decoder can employ iterative decoding and a validity test to generate error indicators. The iterative decoding and validity test can use the lower syndromes.
摘要:
Systems and methods are provided for recovering data stored in memory. A group of data is encoded using a first layer of code to form a first encoded group of data. Individual portions of the first encoded group of data are then encoded using a second layer of code to form a second encoded group of data. A processor may request access to an individual portion of the group of data. The encoded version of the requested individual portion is retrieved from memory and decoded using the second layer of code to recover the requested individual portion. If the recovery of the requested individual portion fails, the remaining encoded portions of the group are retrieved from memory and decoded using the first layer of code to recover the requested individual portion.