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Showing 1 to 20 of 42 for “"LDPC codes"”.
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A sampling technique based on LDPC codes
… scheme based on Low Density Parity Check codes and compare it with existing sampling techniques. The proposed sampling scheme works for discrete variables only, but makes no further assumption of the structure of target distribution. The main idea of the proposed sampling method relies on …
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Mobile Banking Security Using GPS and LDPC Codes
… within mobile devices, and low density parity codes (LDPC). The approach is to determine a user's daily locations, set them as trusted locations, and use LDPC codes not only to obscure this data from attackers, but to help in correcting inaccurate GPS readings. The conclusions, based on …
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Importance sampling for LDPC codes and turbo-coded CDMA
Low-density parity-check (LDPC) codes have shown capacity-approaching performance with soft iterative decoding algorithms. Simulating LDPC codes at very low error rates normally takes an unacceptably long time. We consider importance sampling (IS) schemes for the error rate estimation of LDPC …
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LP/SDP hierarchy lower bounds for decoding random LDPC codes
Random (dv, dc)-regular LDPC codes (where each variable is involved in d, parity checks and each parity check involves d, variables) are well-known to achieve the Shannon capacity of the binary symmetric channel (for sufficiently large dv, and dc,) under exponential time decoding. However, …
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The Analysis of Error Floor and Graphical Structure of LDPC Codes
… for counting them in the Tanner graph of LDPC codes, one for Tanner graphs of general LDPC codes, and one tailored for Tanner graphs of practically important quasi cyclic (QC) protograph LDPC codes.We show that for sparse graphs, the proposed algorithms significantly outperform the …
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Novel irregular LDPC codes and their application to iterative detection of MIMO systems
Low-density parity-check (LDPC) codes are among the best performing error correction codes currently known. For higher performing irregular LDPC codes, degree distributions have been found which produce codes with optimum performance in the infinite block length case. Significant performance …
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Error Floor Analysis of Quasi-Cyclic LDPC and Spatially Coupled-LDPC Codes and Construction of Codes with Low Error Floor
Forward error-correcting (FEC) codes play an important role in transmitting data with extremely high reliability through modern communication systems. In this thesis, we study the design and analysis of low-density parity-check (LDPC) codes in general and spatially coupled (SC) LDPC codes, in …
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Single and joint iterative decoding for higher order modulation schemes
… in particular, low-density parity-check (LDPC) codes, iterative decoding on Tanner graphs, and their application on joint iterative receivers based on the turbo principle, previously proposed. The construction of random LDPC codes that fulfil certain desirable characteristics, such as …
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Trapping Sets of Iterative Decoders for Quantum and Classical Low-Density Parity-Check Codes
… or quantum computation. Error correction codes and their decoders perform this step by adding redundant information that aids the decoder to recover or protect the logical information even in the presence of noise. Low-density parity-check (LDPC) codes have been one of the most popular …
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VLSI Architectures for Iterative Channel Decoders
Decoder architectures for LDPC codes introduce another complexity dimension related to the on-chip interconnect bottleneck of LDPC decoders. A new parameterized-core-based design methodology targeted for scalable and programmable LDPC decoders is proposed. The methodology solves the problems of …
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On the construction of some capacity-approaching coding schemes
… scheme is based on low-density parity-check (LDPC) codes. We first demonstrate that we can translate threshold values of an LDPC code between channels accurately using a simple mapping. We develop some models for density evolution from this observation, namely erasure-channel, …
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Iterative algorithms for lossy source coding
… coding, we analyze low density parity check (LDPC) codes and low density generator matrix (LDGM) codes for quantization under a Hamming distortion. We prove that LDPC codes can achieve the rate-distortion function. We also show that the variable node degree of any LDGM code must become …
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An Information Theoretic Study on Linear Dispersion Codes and Low -Density Parity -Check Codes
… theoretic study of linear dispersion (LD) codes and low-density parity-check (LDPC) codes. For bit-linear LD codes, we find necessary and sufficient conditions on the dispersion matrices for the a posteriori distribution of the information bit vector to be a product distribution. We also …
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Field-programmable gate-array (FPGA) implementation of low-density parity-check (LDPC) decoder in digital video broadcasting - second generation satellite (DVB-S2)
In recent years, LDPC codes are gaining a lot of attention among researchers. Its near-Shannon performance combined with its highly parallel architecture and lesser complexity compared to Turbo-codes has made LDPC codes one of the most popular forward error correction (FEC) codes in most of the …
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Near-capacity fixed-rate and rateless channel code constructions
… conflicting design tradeoffs, leading to codes that benefit from practical implementations, whilst offering a good bit error ratio (BER) and block error ratio (BLER) performance. More explicitly, two novel low-density parity-check code (LDPC) constructions are proposed; the first …
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Joint Equalization and Decoding via Convex Optimization
… decoding problem for low-density parity-check (LDPC) codes on finite-state channels (FSCs). Hard-disk drives (or magnetic recording systems), where the required error rate (after decoding) is too low to be verifiable by simulation, are most important applications of this research. Recently, LDPC …
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Low-density parity-check codes : construction and implementation.
Low-density parity-check (LDPC) codes have been shown to have good error correcting performance approaching Shannon’s limit. Good error correcting performance enables efficient and reliable communication. However, a LDPC code decoding algorithm needs to be executed efficiently to meet cost, time, …
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Efficient Information Reconciliation for Quantum Key Distribution = Reconciliación eficiente de información para la distribución cuántica de claves
… we propose the use of low-density parity-check (LDPC) codes, since they are good both in efficiency and throughput. A price to pay, a priori, using LDPC codes is that good efficiency is only attained for very long codes and in a very narrow range of error rates. This forces to use several codes …
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Code design for the relay channel
… we propose dual-rate low-density parity-check (LDPC) codes. In our designs, the source transmission is decoded with the help of side information in the form of additional parity bits from the relay. The key challenge is to discover codes that simultaneously perform well for the source-relay and …
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