A problem in designing semiconductor memories is to provide some measure of errorcontrol without requiring excessive coding overhead or decoding time. In LSI and VLSI technology, memories are often organized on a mul...
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A problem in designing semiconductor memories is to provide some measure of errorcontrol without requiring excessive coding overhead or decoding time. In LSI and VLSI technology, memories are often organized on a multiple bit (or byte) per chip basis. For example, some 256K bit DRAM"s are organized in 32K Ã? 8 bit-bytes. Byte-oriented codes such as Reed-Solomon (RS) codes can provide efficient low overhead errorcontrol for such memories. However, the standard iterative algorithm for decoding RS codes is too slow for these applications. In this correspondence we present a special decoding technique for double-byte-error-correcting (DBEC), triple-byte-error-detecting (TBED) RS codes which is capable of high-speed operation. This technique is designed to find the error locations and the error values directly from the syndrome without having to use the iterative algorithm to find the error locator polynomial.
In this paper we propose a biometric cryptosystem able to provide security and renewability to a function based on-line signature representation. A novel reliable signature traits selection procedure, along with a sig...
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In this paper we propose a biometric cryptosystem able to provide security and renewability to a function based on-line signature representation. A novel reliable signature traits selection procedure, along with a signature binarization algorithm, are introduced. Experimental results, evaluated on the public MCYT signature database, show that the proposed protected on-line signature recognition system guarantees recognition rates comparable with those of unprotected approaches, and outperforms already proposed protection schemes for signature biometrics.
To achieve a high track density, two-dimensional magnetic recording (TDMR) is combined with shingled magnetic recording (SMR). SMR makes it possible to record 1 bit on a few grains. However, the performance will be re...
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To achieve a high track density, two-dimensional magnetic recording (TDMR) is combined with shingled magnetic recording (SMR). SMR makes it possible to record 1 bit on a few grains. However, the performance will be remarkably deteriorated by the increased media noise, the inter-track and inter-symbol interference (ITI and ISI). Therefore, the application of effective equalization and error control coding are required. In this paper, we investigate a simple block-based neural network equalizer (NNE) that mitigates the influence of ITI and ISI. We compare the equalization effects of the NNE and a conventional 2-D equalizer with low-density parity-check (LDPC) coding based on a random Voronoi grain media model. Simulation results show the proposed block-based NNE achieves better bit error rate performance than the conventional 2-D linear equalizer followed by the a posteriori probability (APP) detector and a sum-product (SP) decoder. In addition, we find the block-based NNE is sensitive to write errors.
This letter presents a novel low-complexity decoder for turbo product codes (TPCs). The new decoder, denoted as ultra-light decoder (ULD), can perform soft-decision decoding without an algebraic hard decision decoder,...
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This letter presents a novel low-complexity decoder for turbo product codes (TPCs). The new decoder, denoted as ultra-light decoder (ULD), can perform soft-decision decoding without an algebraic hard decision decoder, which is the core of conventional soft-decision decoders of block codes. Moreover, the unique structure of the ULD enables the design of a new approach to compute the minimum Euclidean distance at each decoding iteration. Therefore, the ULD offers significant complexity and delay reduction as compared with the conventional TPC decoders. Reducing the complexity and delay will enable using codes with high code rates to improve the system spectral efficiency or use powerful codes with low code rates to reduce the transmission power. The system bit-error rate is presented for binary and M-ary modulation schemes over additive white Gaussian noise channels, and the coding gain is given for Rayleigh fading channels. The obtained numerical results show that the ULD offers coding gain that is comparable to the conventional TPC decoders under various system and channel conditions but with significantly lower complexity.
Discrete Fourier transform codes (DFT codes) or real number codes have been studied and recognized as useful (as joint source-channel codes, for example) but are not stable under bursty losses. This letter introduces ...
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Discrete Fourier transform codes (DFT codes) or real number codes have been studied and recognized as useful (as joint source-channel codes, for example) but are not stable under bursty losses. This letter introduces a two-channel DFT code with an interleaver and shows that its numerical stability far exceeds that of the corresponding single-channel DFT code (the ratio of the frame bounds for the two-channel system can be smaller by many orders of magnitude). This leads to a stable way of dealing with bursts of errors using DFT codes.
In this paper the robustness of the physical layer signaling in the new DVB-T2 (second generation terrestrial digital video broadcasting) system is studied and compared to corresponding robustness of data path with he...
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In this paper the robustness of the physical layer signaling in the new DVB-T2 (second generation terrestrial digital video broadcasting) system is studied and compared to corresponding robustness of data path with help of computer simulations. The robustness is studied in both static and mobile transmission channels.
Shortening is a widely used technique aiming mainly to reduce the block size of an error correcting code and at the same time to enhance its efficiency. However, due to a common misapprehension, students tend to belie...
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Shortening is a widely used technique aiming mainly to reduce the block size of an error correcting code and at the same time to enhance its efficiency. However, due to a common misapprehension, students tend to believe that maximum shortening retains maximum coding efficiency. In this work, an educational approach is presented which eliminates the aforementioned misapprehension. Specifically, the efficiency of the shortened error correcting codes is examined both theoretically and experimentally via simulations.
In this paper, we present a unified approach for optimum frame synchronization where the observed symbols are modeled as the output of a Markov chain corrupted by additive white Gaussian noise (AWGN). This model encom...
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In this paper, we present a unified approach for optimum frame synchronization where the observed symbols are modeled as the output of a Markov chain corrupted by additive white Gaussian noise (AWGN). This model encompasses many different frame synchronization situations e.g., convolutionally coded transmissions and nonlinear modulations with memory, such as continuous-phase modulation. The proposed frame synchronizer is implemented with trellis path search used for Markov chain decoding and provides better performance than conventional synchronizers because it is able to exploit coding gain. The proposed synchronizer includes many previously proposed synchronizers either as special cases or as suboptimal approximations. The numerical results show the performance gain of the proposed frame synchronizer for convolutional codes with linear modulation, transmission over known intersymbol-interference channels, and nonlinear continuous-phase modulation signals. The proposed frame synchronizer is derived for the case of continuous transmission but may also be applied to certain packet transmission scenarios.
Digital data transmission and storage are indispensable components for our contemporary information-driven society. As data volumes keep increasing, the need for efficient coding schemes grows. This paper gives a nove...
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Digital data transmission and storage are indispensable components for our contemporary information-driven society. As data volumes keep increasing, the need for efficient coding schemes grows. This paper gives a novel coding scheme for generating sixteen codes from generators with quaternary codes, thereby offering a significant increase in data representation capacity, new possibilities for data encoding and decoding, and an overall improvement in the efficiency of the encoding scheme. This provides up a new perspective for numerous fields that can profit from the proposed scheme, including coding theory, computer science, modeling, and experimental design. We focus on only experimental design and modeling, due to space limits and their importance in designing and modeling real-world and scientific phenomena. The main findings indicate that the new generated sixteen codes can be used as optimal experimental designs with good space-filling behavior when designing large-scale experiments, and as efficient datasets that perform well in fitting various functions even with a small number of points and without modeling assumptions. The relationships between the codewords of the generated sixteen codes and the codewords of the generator quaternary codes are investigated. These relationships provide a benchmark by which to select the generator most efficiently, resulting in codewords that are efficient from multiple angles. Furthermore, the space-filling behavior and isomorphism examination of the sixteen codes generated as designs are deeply theoretically studied.
Turbo product codes (TPCs) have been integrated in several practical applications, and hence, they have been considered widely in the literature where the main aim is improving the error performance and/or reducing th...
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Turbo product codes (TPCs) have been integrated in several practical applications, and hence, they have been considered widely in the literature where the main aim is improving the error performance and/or reducing the computational and implementation complexity. This paper presents a comprehensive survey of the research that focuses on TPCs in terms of encoding, decoding, error performance, and complexity. Moreover, this paper also considers the advantages of integrating TPCs in hybrid automatic repeat request systems where power optimization becomes very efficient and the complexity can be reduced using the unique properties of TPCs such as error self-detection capabilities. Based on the surveyed literature, the pivotal open research issues in TPCs are presented and discussed.
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