Channel Coding Methods For Non Volatile Memories
DOWNLOAD
Download Channel Coding Methods For Non Volatile Memories PDF/ePub or read online books in Mobi eBooks. Click Download or Read Online button to get Channel Coding Methods For Non Volatile Memories book now. This website allows unlimited access to, at the time of writing, more than 1.5 million titles, including hundreds of thousands of titles in various foreign languages. If the content not found or just blank you must refresh this page
Channel Coding Methods For Non Volatile Memories
DOWNLOAD
Author : Lara Dolecek
language : en
Publisher:
Release Date : 2016
Channel Coding Methods For Non Volatile Memories written by Lara Dolecek and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2016 with Coding theory categories.
"Non-volatile memories (NVMs) have emerged as the primary replacement of hard-disk drives for a variety of storage applications, including personal electronics, mobile computing, intelligent vehicles, enterprise storage, data warehousing, and data-intensive computing systems. Channel coding schemes are a necessary tool for ensuring target reliability and performance of NVMs. However, due to operational asymmetries in NVMs, conventional coding approaches - commonly based on designing for the Hamming metric - no longer apply. Given the immediate need for practical solutions and the shortfalls of existing methods, the fast-growing discipline of coding for NVMs has resulted in several key innovations that not only answer the needs of modern storage systems but also directly contribute to the analytical toolbox of coding theory at large. This monograph discusses recent advances in coding for NVMs, covering topics such as error correction coding based on novel algebraic and graph-based methods, rank modulation, rewriting codes, and constrained coding. Our goal for this work is multifold: to illuminate the advantages - as well as challenges - associated with modern NVMs, to present a succinct overview of several exciting recent developments in coding for memories, and, by presenting numerous potential research directions, to inspire other researchers to contribute to this timely and thriving discipline."--Publisher.
Channel Coding Methods For Non Volatile Memories
DOWNLOAD
Author : Lara Dolecek
language : en
Publisher:
Release Date : 2016
Channel Coding Methods For Non Volatile Memories written by Lara Dolecek and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2016 with Coding theory categories.
Non-volatile memories (NVMs) have emerged as the primary replacement of hard-disk drives for a variety of storage applications, including personal electronics, mobile computing, intelligent vehicles, enterprise storage, data warehousing, and data-intensive computing systems. Channel coding schemes are a necessary tool for ensuring target reliability and performance of NVMs. However, due to operational asymmetries in NVMs, conventional coding approaches - commonly based on designing for the Hamming metric - no longer apply. Given the immediate need for practical solutions and the shortfalls of existing methods, the fast-growing discipline of coding for NVMs has resulted in several key innovations that not only answer the needs of modern storage systems but also directly contribute to the analytical toolbox of coding theory at large. This monograph discusses recent advances in coding for NVMs, covering topics such as error correction coding based on novel algebraic and graph-based methods, rank modulation, rewriting codes, and constrained coding. Our goal for this work is multifold: to illuminate the advantages - as well as challenges - associated with modern NVMs, to present a succinct overview of several exciting recent developments in coding for memories, and, by presenting numerous potential research directions, to inspire other researchers to contribute to this timely and thriving discipline.
Channel And Source Coding For Non Volatile Flash Memories
DOWNLOAD
Author : Mohammed Rajab
language : en
Publisher: Springer Nature
Release Date : 2020-01-02
Channel And Source Coding For Non Volatile Flash Memories written by Mohammed Rajab and has been published by Springer Nature this book supported file pdf, txt, epub, kindle and other format this book has been release on 2020-01-02 with Computers categories.
Mohammed Rajab proposes different technologies like the error correction coding (ECC), sources coding and offset calibration that aim to improve the reliability of the NAND flash memory with low implementation costs for industrial application. The author examines different ECC schemes based on concatenated codes like generalized concatenated codes (GCC) which are applicable for NAND flash memories by using the hard and soft input decoding. Furthermore, different data compression schemes are examined in order to reduce the write amplification effect and also to improve the error correct capability of the ECC by combining both schemes.
Error Correction Codes For Non Volatile Memories
DOWNLOAD
Author : Rino Micheloni
language : en
Publisher: Springer Science & Business Media
Release Date : 2008-06-03
Error Correction Codes For Non Volatile Memories written by Rino Micheloni and has been published by Springer Science & Business Media this book supported file pdf, txt, epub, kindle and other format this book has been release on 2008-06-03 with Technology & Engineering categories.
Nowadays it is hard to find an electronic device which does not use codes: for example, we listen to music via heavily encoded audio CD's and we watch movies via encoded DVD's. There is at least one area where the use of encoding/decoding is not so developed, yet: Flash non-volatile memories. Flash memory high-density, low power, cost effectiveness, and scalable design make it an ideal choice to fuel the explosion of multimedia products, like USB keys, MP3 players, digital cameras and solid-state disk. In ECC for Non-Volatile Memories the authors expose the basics of coding theory needed to understand the application to memories, as well as the relevant design topics, with reference to both NOR and NAND Flash architectures. A collection of software routines is also included for better understanding. The authors form a research group (now at Qimonda) which is the typical example of a fruitful collaboration between mathematicians and engineers.
Novel Coding Strategies For Multi Level Non Volatile Memories
DOWNLOAD
Author : Frederic Sala
language : en
Publisher:
Release Date : 2013
Novel Coding Strategies For Multi Level Non Volatile Memories written by Frederic Sala and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2013 with categories.
Non-volatile memories (NVMs) are the most important modern data storage technology. Despite their significant advantages, NVMs suffer from poor reliability due to issues such as voltage drift over time, overwriting, and inter-cell coupling. This thesis applies coding-theoretic techniques to NVMs in order to improve their reliability and extend their lifetimes. In particular, we focus on two classes of problems: those related to the use of thresholds to read memory cells, and those related to inter-cell coupling in the data representation scheme known as rank modulation. The first part of the thesis develops the concept of dynamic thresholds. In NVMs, reading stored data is typically done by comparing cell values against a set of predetermined, fixed threshold references. However, due to common NVM problems, fixed threshold usage often results in significant asymmetric errors. To combat these problems, the notion of dynamic thresholds was recently introduced. Such thresholds are allowed to change in order to react to changes in cell value distributions. Thus far, dynamic thresholds have been applied to the reading of binary sequences in memories with single-level cells (SLCs). In this work, the use of dynamic thresholds for multi-level cell (MLC) memories is explored. A general scheme to compute and apply dynamic thresholds is provided. We derive a series of performance results, based on both practical considerations and theoretical analysis. We show that the proposed threshold scheme compares favorably with the best-possible threshold scheme. Finally, we develop error-correcting codes that are tailored to take advantage of the properties of dynamic thresholds. Code constructions are provided for different channel models, including those allowing limited and unlimited numbers of errors of varying magnitude limitations. The second part of this thesis is focused on the application of constrained coding to rank modulation. Rank modulation is an MLC NVM scheme where information is represented by the rankings of charge levels in an entire block of cells, rather than the absolute charge level of any particular cell. This scheme resolves certain NVM problems, including write-asymmetry, as it allows for a transition from any information state to any other solely through the addition of charge to an appropriate subset of cells. However, the scheme still suffers from inter-cell coupling errors. Such errors are due to inadvertent charge level increases in cells whose neighboring cells have significantly larger levels. We introduce constraints that mitigate the inter-cell coupling problem in rank modulation. These constraints typically limit the differences between the ranks of neighboring elements in a permutation, and thus limit the charge level differences between adjacent cells, reducing inter-cell coupling effects. In particular, we analyze the single neighbor k-constraint, where neighboring cells' ranks cannot differ by more than k. We provide the best-known bounds for the sizes of sets meeting this constraint, and, for certain cases where the parameter k involves a constant term, we derive exact expressions. We perform an asymptotic analysis. Lastly, we introduce an efficient scheme that allows us to systematically generate constrained permutations.
Coding Assisted Methods For Crossbar Resistive Memory
DOWNLOAD
Author : Zehui Chen
language : en
Publisher:
Release Date : 2021
Coding Assisted Methods For Crossbar Resistive Memory written by Zehui Chen and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2021 with categories.
Living in the era of big-data, it is crucial to store vast amounts of data and process them quickly. Resistive random-access memory (ReRAM) with the crossbar structure is one promising candidate to be used as the next generation non-volatile memory device and is also one essential enabler for accelerators that can drastically increase data processing speed. In this work, we tackle problems in crossbar resistive memory and its accelerator application based on channel coding theory and estimation theory. In Chapter 2, under the non-negligible device variability in practical resistive memory, we treat the problem of Hamming distance computation between two vectors, using low-level conductance measurement, based on a novel \textit{Computation-in-Memory} architecture, which has shown great potential in reducing the burden of massive data processing by bypassing the communication and memory access bottleneck. We study the feasibility problem of Hamming distance computation in-memory under two distinct sources of memristor variability: resistance variation, and the non-deterministic write process. First, we introduce a technique for estimating the Hamming distance under resistance variation. Then, we propose error-detection and error-correction schemes to deal with the non-ideal write process. These results are then combined to concurrently address both sources of variabilities. Lastly, we demonstrate the efficacy of our approaches on the k-nearest neighbors classifier, a machine learning algorithm that can be accelerated by computing Hamming distance in-memory. In Chapter 3, considering unreliable selection devices, we study mitigation techniques for the re-occurred sneak-path problem. In a crossbar ReRAM, in which a memristor is positioned on each row-column intersection, the sneak-path problem is one of the main challenges for a reliable readout. The sneak-path problem can be solved with additional selection devices. When some selection devices fail short, the sneak-path problem re-occurs. The re-occurred sneak-path event can be described combinatorially and its adverse effect can be modeled as a parallel interference. Based on a simple pilot construction, we probabilistically characterize the inter-cell dependency of the re-occurred sneak-path events. Utilizing this dependency, we propose adaptive thresholding schemes for resistive memory readout using side information provided by pilot cells. This estimation theoretic approach effectively reduces the bit-error rate while maintaining low redundancy overhead and low complexity. In Chapter 4, dealing with the increasing resistivity of wordline/bitline in crossbar resistive memory as a result of the scaled down technology node, we propose write/read communication channels under high line resistance and coding theoretic solutions tailored for this channel, targeting the storage class memory (SCM) application. By statistically relating the degraded write/read margins and the channel parameters, we propose binary asymmetric channel (BAC) models for the write/read operations. Method for optimizing the read threshold is proposed to reduce the raw bit-error rate (RBER). Observing a large non-uniformity of reliabilities in the memory array, we propose two schemes for efficient channel coding based on Bose-Chaudhuri-Hocquenghem (BCH) codes. An interleaved coding scheme is proposed to mitigate the non-uniformity of reliability and a location dependent coding framework is proposed to leverage this non-uniformity. Both of our proposed coding schemes effectively reduce the undetected bit-error rate (UBER).
Algorithms And Data Representations For Emerging Non Volatile Memories
DOWNLOAD
Author : Yue Li
language : en
Publisher:
Release Date : 2015
Algorithms And Data Representations For Emerging Non Volatile Memories written by Yue Li and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2015 with categories.
The evolution of data storage technologies has been extraordinary. Hard disk drives that fit in current personal computers have the capacity that requires tons of transistors to achieve in 1970s. Today, we are at the beginning of the era of non-volatile memory (NVM). NVMs provide excellent performance such as random access, high I/O speed, low power consumption, and so on. The storage density of NVMs keeps increasing following Moore's law. However, higher storage density also brings significant data reliability issues. When chip geometries scale down, memory cells (e.g. transistors) are aligned much closer to each other, and noise in the devices will become no longer negligible. Consequently, data will be more prone to errors and devices will have much shorter longevity. This dissertation focuses on mitigating the reliability and the endurance issues for two major NVMs, namely, NAND flash memory and phase-change memory (PCM). Our main research tools include a set of coding techniques for the communication channels implied by flash memory and PCM. To approach the problems, at bit level we design error correcting codes tailored for the asymmetric errors in flash and PCM, we propose joint coding scheme for endurance and reliability, error scrubbing methods for controlling storage channel quality, and study codes that are inherently resisting to typical errors in flash and PCM; at higher levels, we are interested in analyzing the structures and the meanings of the stored data, and propose methods that pass such metadata to help further improve the coding performance at bit level. The highlights of this dissertation include the first set of write-once memory code constructions which correct a significant number of errors, a practical framework which corrects errors utilizing the redundancies in texts, the first report of the performance of polar codes for flash memories, and the emulation of rank modulation codes in NAND flash chips. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/152646
Combined Source And Channel Coding For Non Volatile Flash Memories Kombinierte Quellen Und Kanalcodierung F R Flash Speicher
DOWNLOAD
Author : Jürgen Freudenberger
language : en
Publisher:
Release Date : 2019
Combined Source And Channel Coding For Non Volatile Flash Memories Kombinierte Quellen Und Kanalcodierung F R Flash Speicher written by Jürgen Freudenberger and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2019 with categories.
Combinatorial Optimization And Applications
DOWNLOAD
Author : Xiaofeng Gao
language : en
Publisher: Springer
Release Date : 2017-12-06
Combinatorial Optimization And Applications written by Xiaofeng Gao and has been published by Springer this book supported file pdf, txt, epub, kindle and other format this book has been release on 2017-12-06 with Computers categories.
The two-volume set LNCS 10627 and 10628 constitutes the refereed proceedings of the 11th International Conference on Combinatorial Optimization and Applications, COCOA 2017, held in Shanghai, China, in December 2017. The 59 full papers and 19 short papers presented were carefully reviewed and selected from 145 submissions. The papers cover most aspects of theoretical computer science and combinatorics related to computing, including classic combinatorial optimization, geometric optimization, complexity and data structures, and graph theory. They are organized in topical sections on network, approximation algorithm and graph theory, combinatorial optimization, game theory, and applications.
Channel Coding Techniques For Communication Over Networks And Over Channels With Memory
DOWNLOAD
Author : Nadim Ghaddar
language : en
Publisher:
Release Date : 2022
Channel Coding Techniques For Communication Over Networks And Over Channels With Memory written by Nadim Ghaddar and has been published by this book supported file pdf, txt, epub, kindle and other format this book has been release on 2022 with categories.
Next-generation wireless communication systems will have to deal with an unprecedented number of communicating users and devices while enabling orders-of-magnitude of performance improvement in speed and connectivity. With the increasingly complex network structure and the high spectral efficiency requirements, it becomes extremely inefficient to rely on traditional channel coding paradigms that do not take into account the structure of the network and its inherent properties. Unlike conventional channel coding schemes that are designed under the assumption of a single sender and a single receiver communicating over a memoryless channel, this dissertation investigates low-complexity channel coding techniques that take advantage of the number of communicating devices in a network and the inherent memory in the channel. In communication over networks, low-complexity channel coding schemes that achieve the best known information theoretic performance are constructed starting from simple coding blocks. In communication over channels with memory, practical channel coding techniques that exploit the memory in the channel are developed. In both cases, the proposed coding techniques have the potential of addressing the increasing-spectral-efficiency requirement in next-generation wireless communication systems.