Systems and methods for decoding block and concatenated codes are provided. These include advanced iterative decoding techniques based on belief propagation algorithms, with particular advantages when applied to codes having higher density parity check matrices. Improvements are also provided for performing channel state information estimation including the use of optimum filter lengths based on channel selectivity and adaptive decision-directed channel estimation. These improvements enhance the performance of various communication systems and consumer electronics. Particular improvements are also provided for decoding HD Radio signals, including enhanced decoding of reference subcarriers based on soft-diversity combining, joint enhanced channel state information estimation, as well as iterative soft-input soft-output and list decoding of convolutional codes and Reed-Solomon codes. These and other improvements enhance the decoding of different logical channels in HD Radio systems.

Systems and methods for advanced iterative decoding and channel estimation of concatenated coding systems

An accelerated erasure coding system includes a processing core for executing computer instructions and accessing data from a main memory, and a non-volatile storage medium for storing the computer instructions. The processing core, storage medium, and computer instructions are configured to implement an erasure coding system, which includes: a data matrix for holding original data in the main memory; a check matrix for holding check data in the main memory; an encoding matrix for holding first factors in the main memory, the first factors being for encoding the original data into the check data; and a thread for executing on the processing core. The thread includes: a parallel multiplier for concurrently multiplying multiple entries of the data matrix by a single entry of the encoding matrix; and a first sequencer for ordering operations through the data matrix and the encoding matrix using the parallel multiplier to generate the check data.

Accelerated erasure coding system and method

A nonvolatile memory storage controller for delivering log likelihood ratios (LLRs) to a low-density parity check (LDPC) decoder for use in the decoding of an LDPC encoded codeword. The controller includes partitioning circuitry for identifying a set of soft-decision reference voltages having the smallest calculated introduced error value based upon the estimated BER of the nonvolatile memory. The controller further includes read circuitry for reading an LDPC encoded codeword stored in a nonvolatile memory storage module using the set of soft-decision reference voltages having the smallest calculated LLR introduced error value to provide a plurality of soft-decision bits representative of the codeword. The controller further includes an LLR look-up table accessible by the read circuitry to provide LLRs to the LDPC decoder for the subsequent decoding of the codeword.

System and method with reference voltage partitioning for low density parity check decoding

A system for software error-correcting code (ECC) protection or compression of original data using ECC data in a first memory is provided. The system includes a processing core for executing computer instructions and accessing data from a main memory, and a non-volatile storage medium for storing the computer instructions. The software ECC protection or compression includes: a data matrix for holding the original data in the first memory; a check matrix for holding the ECC data in the first memory; an encoding matrix for holding first factors in the main memory, the first factors being for encoding the original data into the ECC data; and a thread for executing on the processing core. The thread includes a Galois Field multiplier for multiplying entries of the data matrix by an entry of the encoding matrix, and a sequencer for ordering operations using the Galois Field multiplier to generate the ECC data.

Using parity data for concurrent data authentication, correction, compression, and encryption

A data storage device reads a data unit from a memory page, detects a number of data bit errors in the data unit, and generates a bit error indicator identifying bit indexes of the data bit errors in the data unit. The data storage device reads the data unit from the memory page once again and generates a corrected data unit by correcting data bit errors in the data unit based on the error correction code if the number of data bit errors in the data unit does not exceed an error correction capacity of the error correction code. Otherwise, the data storage device generates a modified data unit based on the data unit by negating at least one erroneous data bit the data unit based on the bit error indicator and corrects any remaining data bit errors in the modified data unit based on the error correction code.

Error correction code technique for improving read stress endurance

Systems and methods are provided for implementing various aspects of 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. If the decision-codeword corresponds to an inner code and an RS code is the outer code, a soft-information map can process the soft-information for the decision-codeword to produce soft-information for a RS decision-codeword. A RS decoder can employ the Berlekamp-Massey algorithm (BMA), list decoding, and a Chien search, and can include a pipelined architecture. A threshold-based control circuit can be used to predict whether list decoding will be needed and can suspend the list decoding operation if it predicts that list decoding is not needed.

Architecture and control of reed-solomon error-correction decoding

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.

Architecture and control of reed-solomon list decoding

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

Tony Yoon

Papers

Architecture and control of reed-solomon error-correction decoding

Architecture and control of reed-solomon list decoding

Architecture and control of reed-solomon error identification and evaluation