• Title/Summary/Keyword: Error correction code

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16×2.5 Gb/s WDM transmission over 10,880 km using forward error correction (40 Gb/s (16×2.5 Gb/s WDM 신호의 10,880 km 전송실험)

  • 정윤철;전상배;정환석;윤천주;박근주
    • Korean Journal of Optics and Photonics
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    • v.13 no.2
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    • pp.113-116
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    • 2002
  • We demonstrate 16 ch.$\times$2.5 Gb/s WDM transmission over 10,880 km using a re-circulating loop and forward error correction (FEC) code. The performances of all 16 channels were measured to be lower than 10$^{-10}$ .

The Design of Reliable Graphics-DTV Signal Converter Using EDAC Algorithm in DTV System

  • Ryoo, Dong-Wan;Lee, Jeun-Woo
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.2126-2130
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    • 2003
  • In the integrated systems, that is integrated digital TV(DTV) internet and home automation, like home server, is needed integration of digital TV video signal and computer graphic signal. The graphic signal is operating at the high speed and has time-divide-stream. So the re-request of data is not easy at the time of error detection. therefore EDAC algorithm is efficient. In this paper, we show a scheme, that is integration of graphic and dtv format signal for DTV monitor display. This paper also presents the efficiency error detection auto correction(EDAC) for conversion of graphics signal to DTV video signal. A presented EDAC algorithms use the modified hamming code for enhancing video quality and reliability. A EDAC algorithm of this paper can detect single error, double error, triple error and more error for preventing from incorrect correction. And it is not necessary an additional memory. In this paper The comparison between digital TV video signal and graphic signal, a EDAC algorithm and a design of conversion graphic signal to DTV signal with EDAC function in DTV system is described.

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Low-Complexity Triple-Error-Correcting Parallel BCH Decoder

  • Yeon, Jaewoong;Yang, Seung-Jun;Kim, Cheolho;Lee, Hanho
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.13 no.5
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    • pp.465-472
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    • 2013
  • This paper presents a low-complexity triple-error-correcting parallel Bose-Chaudhuri-Hocquenghem (BCH) decoder architecture and its efficient design techniques. A novel modified step-by-step (m-SBS) decoding algorithm, which significantly reduces computational complexity, is proposed for the parallel BCH decoder. In addition, a determinant calculator and a error locator are proposed to reduce hardware complexity. Specifically, a sharing syndrome factor calculator and a self-error detection scheme are proposed. The multi-channel multi-parallel BCH decoder using the proposed m-SBS algorithm and design techniques have considerably less hardware complexity and latency than those using a conventional algorithms. For a 16-channel 4-parallel (1020, 990) BCH decoder over GF($2^{12}$), the proposed design can lead to a reduction in complexity of at least 23 % compared to conventional architecttures.

A Study on EUROFIX Reed Solomon Code Design Using Finite Galois Field Fourier Transformation (유한체 푸리에 변환을 이용한 EUROFIX RS Code 설계에 관한 연구)

  • Kim, Min-Jee;Kim, Min-Jung;Chung, Se-Mo;Cho, Hyung-Rae
    • Journal of Navigation and Port Research
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    • v.28 no.1
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    • pp.23-29
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    • 2004
  • This paper deals with Reed-Solomon Coding for EUROFIX system EUROFIX is an integrated navigation and communication system, which combines Differential GNSS and Loran-C EUROFIX transmits DGNSS(Differential Global Navigation Satellite Systems) (data by pulse position modulation of Loran-C pulses. Loran-C system is regarded as a satellite backup system in recent. And now, it is important to detect and correct much errors in communication systems. Error corrections or correction algorithm is actively studied nowadays because of this. In this paper, we study and design encoder and decoder of Reed Solomon Code using Finite Galois Field Fourier Transformation for error corrections in EUROFIX data transmission. Through extensive simulation, the designed Reed Solomon code is shown to be effective for error correction in EUROFIX data transmission.

Development of Elementary learning materials for Data error detection and correction (데이터 에러 검출과 수정에 대한 초등교육자료 개발)

  • Ko, Hyeongcheol;Kim, Chongwoo
    • Journal of The Korean Association of Information Education
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    • v.22 no.1
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    • pp.169-176
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    • 2018
  • CS Unplugged education at the base of computer science is emphasized as an instrument for teaching the basic principles of elementary SW education, but these materials for elementary education are very lacking. So We'll present the data error detection and correction materials for elementary school classes. Based on previous studies related to this topic, we developed learning materials for elementary higher grade students using Hamming code. We introduces the card magic in the introduction part. 'error detection and correction' learning materials based on the principle of Hamming code, were composed as activity-based education. The results of the questionnaire survey showed that it had a positive effect on improving learners' understanding of computer science.

A Low-Power ECC Check Bit Generator Implementation in DRAMs

  • Cha, Sang-Uhn;Lee, Yun-Sang;Yoon, Hong-Il
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.6 no.4
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    • pp.252-256
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    • 2006
  • A low-power ECC check bit generator is presented with competent DRAM implementation with minimal speed loss, area overhead and power consumption. The ECC used in the proposed scheme is a variant form of the minimum weight column code. The spatial and temporal correlations of input data are analyzed and the input paths of the check bit generator are ordered for the on-line adaptable power savings up to 24.4% in the benchmarked cases. The chip size overhead is estimated to be under 0.3% for a 80nm 1Gb DRAM implementation.

R-S Decoder Design for Single Error Correction and Erasure Generation (단일오류 정정 및 Erasure 발생을 위한 R-S 복호기 설계)

  • Kim, Yong Serk;Song, Dong Il;Kim, Young Woong;Lee, Kuen Young
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.23 no.5
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    • pp.719-725
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    • 1986
  • Reed-solomon(R-S) code is very effective to coerrect both random and burst errors over a noise communication channel. However, the required hardware is very complex if the B/M algorithm was employed. Moreover, when the error correction system consists of two R-S decoder and de-interleave, the I/O data bns lines becomes 9bits because of an erasure flag bit. Thus, it increases the complexity of hardware. This paper describes the R-S decoder which consisits of a error correction section that uses a direct decoding algorithm and erasure generation section and a erasure generation section which does not use the erasure flag bit. It can be shown that the proposed R-S dicoder is very effective in reducing the size of required hardware for error correction.

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An improvement of Simplified Atmospheric Correction : MODIS Visible Channel

  • Lee, Chang-Suk;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
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    • v.25 no.6
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    • pp.487-499
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    • 2009
  • Atmospheric correction of satellite measurements is a major step to estimate accurate surface reflectance of solar spectrum channels. In this study, Simplified Method for the Atmospheric Correction (SMAC) radiative transfer model used to retrieve surface reflectance from MODIS (MODerate resolution Imaging Spectrometer) top of atmosphere (TOA) reflectance. It is fast and simple atmospheric correction method, so it uses for work site operation in various satellite. This study attempts a test of accuracy of SMAC through a sensitivity test to detected error sources and to improve accuracy of surface reflectance using SMAC. The results of SMAC as compared with MODIS surface reflectance (MOD09) was represented that low accuracy ($R^2\;=\;0.6196$, Root Means Square Error (RMSE) = 0.00031, bias = - 0.0859). Thus sensitivity analysis of input parameters and coefficients was conducted to searching error sources. Among the input parameters, Aerosol Optical Depth (AOD) is the most influence input parameter. In order to modify AOD term in SMAC code, Stepwise multiple regression was performed with testing and remove variable in three stages with independent variables of AOD at 550nm, solar zenith angle, viewing zenith angle. Surface reflectance estimation by using Newly proposed AOD term in the study showed that improve accuracy ($R^2\;=\;0.827$, RMSE = 0.00672, bias = - 0.000762).

Performance Analysis of Telemetering Method using Delayed Frame Time Diversity (DFTD) and Reed-Solomon Code (지연프레임 시간다이버시티와 RS 코드를 사용한 원격측정방식의 성능분석)

  • Koh, Kwang-Ryul;Kim, Whan-Woo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.7A
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    • pp.503-511
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    • 2012
  • In this paper, the performance analysis of telemetering method using delayed frame time diversity (DFTD) as the outer code and Reed-Solomon (RS) code as the inner code is described. DFTD is used to transmit a real-time frame together with a time-delayed frame which was saved in the memory during a defined period. The RS code as a kind of FEC (forward error correction) is serially concatenated with DFTD. This method was applied to the design of telemetry units that have been used for flight tests in a communication environment with deep fading. The data of the flight test for four cases with no applied code, with DFTD only, with the RS code only, and with both DFTD and the RS code are used to analyze the performance. The simulation for time-delay suggests the possibility that all frame errors can be removed. And the results of 12 flight tests show the performance superiority of this new method to compare with the RS code only.