• Journal of the Institute of Electronics and Information Engineers
• /
• v.49 no.11
• /
• pp.3-8
• /
• 2012

Two-dimensional product code has been studied for correcting burst errors on the storage systems. An RS-LDPC product code consists of an RS code in horizontal direction and an LDPC code in vertical direction. First, we detect the position of burst errors by using RS code, then LDPC code corrects the errors by using the burst error positions. In storage system, long burst errors are occurred by various reason. So, we need a strong code for correcting the long burst errors. RS-LDPC product code is good for long burst errors. However, as the storage density grows the length of the burst errors will be longer. Thus, we propose an LDPC-LDPC product code, it is strong for correcting the very long burst errors. Also, the proposed LDPC-LDPC product code performs better than RS-LDPC product code when the random errors are occurred, because a row direction LDPC code performs better than row direction RS code.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.8 no.2
• /
• pp.93-106
• /
• 1998

RS부호의 복호 기법은 전체 통신 시스템의 성능 및 복잡도에 큰 영향을 미친다. 지금까지 RS부호의 복호 기법은 다양한 방법에 있으나Euclid알고리즘과 변환복호기법을 이용한 복호 기법은 오류정정능력이 큰 복호 기법으로 널리 적용되고 있다. 본 논문에서는 오류정정능력이 5이상인 RS부호의 복호 알고리즘에 적용될 수 있는 효율적인 복호 알고리즘을 제시하고, 이를 이용하여 5중 오류 정정(31, 21)RS 부호기 및 복호기를 설계하고VHDL을 사용한 컴퓨터 시뮬레션을 통해서 그 타당성을 검증하였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.26 no.9B
• /
• pp.1314-1320
• /
• 2001

최근 전화선과 같이 기존에 존재하는 전송선로를 이용하여 고속의 데이터를 전송할 수 있는 DSL 모뎀 개발에 많은 연구가 활발히 진행되고 있다. DSL 모뎀과 같이 열악한 특성과 제한된 대역폭을 갖는 채널을 통하여 고속의 데이터를 전송하기 위해서는 복잡한 변조방식과 우수한 채널부호(FEC) 알고리즘이 요구된다. 특히, ADSL 시스템 및 VDSL 시스템에서는 다양한 오류정정 능력을 갖는 RS(Reed-Solomon) 부호를 사용하도록 권고하고 있다. 이에 대해, 본 논문에서는 ADSL 및 VDSL 시스템의 권고 안(오류정정 능력(t) = 0∼8)을 만족하는 RS 부호를 한 조의 RS 부호기 및 복호기로 대체할 수 있는 설계구조를 제시한다. 제시된 구조는 8조의 RS 부호가 갖는 면적의 약 23%만으로, t=8인 RS 부호에 대해 약 6%의 추가 면적으로 설계할 수 있다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.2C
• /
• pp.219-228
• /
• 2010

In this paper, performance of RS (Reed-Solomon), turbo and LDPC (low density parity check) code in the binary symmetric erasure channel is investigated. When the average erasure length is reduced, the frequency of short erasures is increased. The RS code shows serious performance degradation in such an environment since decoding is carried out symbol-by-symbol. As the erasure length is increased, however, the RS code shows much improved en-or performance. On the other hand, the message and corresponding parity symbols of the turbo code can be erased at the same time for the long erasures. Accordingly, iterative decoding of the turbo code can not improve error performance any more for such a long erasure. The LDPC code shows little difference in error performance with respect to the variation of the average erasure length due to the virtual interleaving effect. As a result, the LDPC code has much better erasure decoding performance than the RS and turbo code.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.8
• /
• pp.1477-1484
• /
• 2015

In this paper, a novel reversible data hiding by using Reed-Solomon (RS) code is proposed for efficient transmission in encryption image. To increase the recovery of data from encrypted image, RS codes are used to encode messages, and then the codewords can be embedded into encrypted image according to encryption key. After receiving encrypted image which embeds the codewords, the receiver firstly decryptes the encrypted image using the encryption key and get metric about codewords containing messages. According to recovery capability of RS codes, better estimation of message is done in data hiding system. Simulation results about two images and two RS codes show that the performances of the proposed schemes are better than ones of the reference scheme.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.26 no.2
• /
• pp.10-17
• /
• 1989

The Berlekamp-Massey algorithm, the method of using the Euclid algorithm, and Fourier transforms over a finite field can be used for the decoding of Reed-Solomon codes (called RS codes). RS codes can also be decoded by the algorithm that was developed by Peterson and refined by the Gorenstein and Zierler. However, the decoding of RS codes using the Peterson-Gorenstein-Zieler algorithm offers sometimes computational or implementation advantages. The decoding procedure of the double-error correcting (31,27) Rs code over the symbol field GF ($2^5$) will be analyized in this paper. The complete analysis, gate array design, and implementation for encoder/decoder pair of (31.27)RS code are performed with a strong theoretical justification.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.26 no.4B
• /
• pp.427-436
• /
• 2001

RS product codes are widely used in digital storage systems. There are lots of decoding strategies for product code for short-length RS codes. Unfortunately many of them cannot be applied to long-length RS product codes because of the complexity of decoder. This paper proposes new decoding strategies which can be used in long length RS product codes.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.2 no.1
• /
• pp.133-140
• /
• 1998

In this paper, RS coded DTMF modulation for reliable data transmission over mobile fading channels is considered. The circuits of (15,9) RS codec are proposed and synthesized, and the performances are evaluated over fading channels. The codec circuits take about 14000 gates standardized by 2-input NAMD gate. The (15,9) RS coded DTMF signalling provides theoretical coding gain more than 20 dB over fading channels for BER 10.6, the criterion for data transmissions in mobile communications such as IMT-2000. Thus, It is very effective to apply RS codec to DTMF signalling for data transmission in mobile communications over fading channels.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.17 no.7
• /
• pp.730-738
• /
• 1992

This paper alms to analyse the performance of frequency hopping /spread spectrum multiple access system by employing the channel with mixture of AWGN, partial band Jamming, fading and user interference. The performance analysis of FH /SSMA system, taking account of frequency 'hit'(user Interference ) which occurs in the presence of multiple user, produces the following numerical results by computing error probability and throughput of each code in two cases whether the side Information about channel is used or not. The numerical results are as follows : When composite interferences coexist In channel, RS code Is significantly superior to convolutional code in terms of performance. Concatenated code provides the same performance as RS code. The above results show that RS code is pertinent as error-correction code.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.7 no.1
• /
• pp.33-44
• /
• 1997

BISDN(Broadband Integrated Service Digital Network)의 AAL-1(ATM Adaptation Layer-1)에서는 오류정정능력이 2인 (128,124) RS(Reed Slomon) 부호를 이용하여 ATM 셀에서 발생하는 오류를 정정하고 있다. 본 논문에서는 기존의 RS 복호 알고리즘을 분석한 후, 이를 바탕으로 AAL-1 기본오류정정 모드에 적용 가능한 복잡도가 낮고 고속 동작이 가능한 복호 알고리즘을 제시하고, 부호기와 보호기를 VHDL로 부호화하고 설계한 후, 관련 회로를 시뮬레이션한다. 또한 시뮬레이션된 회로를 XACT을 이용하여 XC 4025 FPGA에 실현하여 제안되 복호 알고리즘의 타당성을 확인한다.