• Title/Summary/Keyword: binary codes

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A Direct Decoding Method for Binary BCH Codes (2원 BCH부호의 직접복호법)

  • 염흥렬;이만영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.14 no.1
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    • pp.65-74
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    • 1989
  • This paperr presetns the Direct Decoding Method for binary BCH codes which can find the error locattion number directly from the syndrome without calculating the error locator polynomical. Also in this paper, the triple and quadruple error correcting BCH decoder are designed using this method. As an example, the triple error correcting (63.45) BCH decoder is implemented with TTL ICs. It is shown from our results that this decoder can be implemented with relatively simple hardware.

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A Soft-Decision Decoding Algorithm for Linear Binary Block Codes (線形 2元 블럭 符號를 위한 軟判定 復號 알고리듬)

  • Shim, Yong-Geol;Lee, Choong-Woong
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.2
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    • pp.9-15
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    • 1990
  • A soft-decision decoding algorithm for linear binary block codes is proposed, for minimizing the block error probability. To compare the proposed algorithm with already established decoding methods, computer simulations are performed for the (7,4)Hamming code and the (23,12) Golay code. The average number of hard-decision decoding is always less then 2, and approaches to 1 when the signal to noise ratio is sufficiently large. These results show that the proposed algorithm reduces the decoding complexity.

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Concatenated Coding System for an Effective Error Correction (효율적인 에러 정정을 위한 콘케티네이티드 코팅 시스템)

  • Kang, Beob Joo;Kang, Chang Eon
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.23 no.3
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    • pp.309-316
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    • 1986
  • A concatenated coding system using a binary code as the inner code and a nonbinary code as the outer code has been constructed for the purpose of error correction. The complexity of a conventional coding system grows exponentially as the code length of a block code becomes longer. To reduce the complexity for ling code, an effective communication system has been proposed by cascading two codes-binary and norbinary codes. Using a parallel-to-serial circuit and a serial-to-parallel circuit, the concatenated coding system has been designed and constructed by empolying a (7,3) burst error correcting code as the inner code and a (7,3) Reed-Solomon code as the outer code. This system has been simulated and tested using a micro-computer. For the (49,9) concatenated coding system, the error probability of the channel has been evaluated and compared to different coding systems.

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Iterative Reliability-Based Modified Majority-Logic Decoding for Structured Binary LDPC Codes

  • Chen, Haiqiang;Luo, Lingshan;Sun, Youming;Li, Xiangcheng;Wan, Haibin;Luo, Liping;Qin, Tuanfa
    • Journal of Communications and Networks
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    • v.17 no.4
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    • pp.339-345
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    • 2015
  • In this paper, we present an iterative reliability-based modified majority-logic decoding algorithm for two classes of structured low-density parity-check codes. Different from the conventional modified one-step majority-logic decoding algorithms, we design a turbo-like iterative strategy to recover the performance degradation caused by the simply flipping operation. The main computational loads of the presented algorithm include only binary logic and integer operations, resulting in low decoding complexity. Furthermore, by introducing the iterative set, a very small proportion (less than 6%) of variable nodes are involved in the reliability updating process, which can further reduce the computational complexity. Simulation results show that, combined with the factor correction technique and a well-designed non-uniform quantization scheme, the presented algorithm can achieve a significant performance improvement and a fast decoding speed, even with very small quantization levels (3-4 bits resolution). The presented algorithm provides a candidate for trade-offs between performance and complexity.

A Study of the Interference-Cancelled CDMA System Using Binary ZCD Spreading Codes (이진 ZCD확산코드를 이용한 저간섭 CDMA시스템에 관한 연구)

  • 차재상
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.18 no.4
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    • pp.149-154
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    • 2004
  • In this paper, Interference-Cancelled CDMA system using binary ZCD spreading codes is introduced. Proposed Interference-Cancelled CDMA system can be usefully used for the intra-cellular Interference-Cancelled wireless communication systems. Binary ZCD spreading code sets have various sequence period and family sizes and the ZCD properties of them are very effective for Interference-cancelled CDMA Systems. In this paper, we mathematically analyzed the system performance of our proposed Interference-Cancelled CDMA system in the AWGN channel and various interference environments such as MAI and MPI. Furthermore, using the BER performance simulation we certify the available interference cancellation properties of the proposed system.

Optimum Inner and Outer Code Rates for Concatenated Codes in Gaussian Binary Symmetric Channels (가우시안 이진 대칭 채널에서 쇄상부호의 최적 내.외 부호율에 관한 연구)

  • Lee, Ye Hoon
    • Journal of Satellite, Information and Communications
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    • v.9 no.2
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    • pp.110-113
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    • 2014
  • In this paper, we address a problem of finding the optimum inner and outer code rates for a concatenated code in Gaussian binary symmetric channels. Clearly, as the inner code rate decreases, the error detection capability of the inner code increases. However, decreasing the inner code rate implies a decrease in error-correction capability of the outer code when overall code rate is fixed. With this notion in mind, we examine the optimum distribution of redundancy on the outer and inner codes to achieve a maximum performance gain in the concatenated coding scheme. Our analysis shows that the maximum coding gain can be obtained when the inner code rate is maximized and the outer code rate is minimized under the constraint of total code rate is fixed.

Deep Learning based Dynamic Taint Detection Technique for Binary Code Vulnerability Detection (바이너리 코드 취약점 탐지를 위한 딥러닝 기반 동적 오염 탐지 기술)

  • Kwang-Man Ko
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.16 no.3
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    • pp.161-166
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    • 2023
  • In recent years, new and variant hacking of binary codes has increased, and the limitations of techniques for detecting malicious codes in source programs and defending against attacks are often exposed. Advanced software security vulnerability detection technology using machine learning and deep learning technology for binary code and defense and response capabilities against attacks are required. In this paper, we propose a malware clustering method that groups malware based on the characteristics of the taint information after entering dynamic taint information by tracing the execution path of binary code. Malware vulnerability detection was applied to a three-layered Few-shot learning model, and F1-scores were calculated for each layer's CPU and GPU. We obtained 97~98% performance in the learning process and 80~81% detection performance in the test process.

An LLVM-Based Implementation of Static Analysis for Detecting Self-Modifying Code and Its Evaluation (자체 수정 코드를 탐지하는 정적 분석방법의 LLVM 프레임워크 기반 구현 및 실험)

  • Yu, Jae-IL;Choi, Kwang-hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.32 no.2
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    • pp.171-179
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    • 2022
  • Self-Modifying-Code is a code that changes the code by itself during execution time. This technique is particularly abused by malicious code to bypass static analysis. Therefor, in order to effectively detect such malicious codes, it is important to identify self-modifying-codes. In the meantime, Self-modify-codes have been analyzed using dynamic analysis methods, but this is time-consuming and costly. If static analysis can detect self-modifying-code it will be of great help to malicious code analysis. In this paper, we propose a static analysis method to detect self-modified code for binary executable programs converted to LLVM IR and apply this method by making a self-modifying-code benchmark. As a result of the experiment in this paper, the designed static analysis method was effective for the standardized LLVM IR program that was compiled and converted to the benchmark program. However, there was a limitation in that it was difficult to detect the self-modifying-code for the unstructured LLVM IR program in which the binary was lifted and transformed. To overcome this, we need an effective way to lift the binary code.

Design of New Channel Codes for Speed Up Coding Procedure (코딩 속도향상을 위한 채널 코드의 설계)

  • 공형윤;이창희
    • Proceedings of the IEEK Conference
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    • 2000.06a
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    • pp.5-8
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    • 2000
  • In this paper, we present a new cぉnet coding method, so called MLC (Multi-Level Codes), for error detection and correction in digital wireless communication. MLC coding method we the same coding procedure wed in the convolutional coding but it is distinguished from the existing convolutional coding in point of generating the code word by using multi-level information data (M-ary signal) and in point of speed of coding procedure Through computer simulation, we analyze the performance of the coding method suggested here compared to convolutional coding method in case of modulo-operation and in case of non-binary coding Procedure respectively under various channel environments.

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Hyperparameter Selection for APC-ECOC

  • Seok, Kyung-Ha
    • Journal of the Korean Data and Information Science Society
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    • v.19 no.4
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    • pp.1219-1231
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    • 2008
  • The main object of this paper is to develop a leave-one-out(LOO) bound of all pairwise comparison error correcting output codes (APC-ECOC). To avoid using classifiers whose corresponding target values are 0 in APC-ECOC and requiring pilot estimates we developed a bound based on mean misclassification probability(MMP). It can be used to tune kernel hyperparameters. Our empirical experiment using kernel mean squared estimate(KMSE) as the binary classifier indicates that the bound leads to good estimates of kernel hyperparameters.

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