• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.507-510
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• 2010

OFDM(Orthogonal Frequency Division Multiplexing)은 하나의 데이터 열(data stream)을 낮은 데이터 전송률을 갖는 작은 데이터로 나누고, 이들을 부반송파(subcarrier)를 통해 동시에 전송한다. OFDM이 차세대 전송방식으로 채택된 이유는 주파수 선택적 페이딩(frequency selective fading)이나 협대역(narrow band)간 간섭에 받는 영향이 적어 고속 통신이 가능하기 때문이다. 본 논문에서는 RS 부호(Reed-Solomon Code)를 사용하여 OFDM에서 대용량 데이터를 전송할 때 발생하기 쉬운 연집 오류(burst error)를 정정하도록 하였다. 또한 채널 사이에 파일롯 심볼(pilot symbol)을 삽입하여 채널 추정을 통한 신호의 타이밍 오류도 고려하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.6
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• pp.1575-1582
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• 1998

Reed-Solomon(RS) code which is especially effective against burst error is studied as a forward error correction technique in this ppaer. The circuits of RS encoder and decoder for ASIC implementation are designed and presented employing modified Euclid's algorithm. The functionalities of the designed circuits are verified though C programs which simulates the circuits over the various errors and erasures. The pipelined circuits using systolic arrays are designed for ASIC realization in VHDL, and verified through the logic simulations. Finally the circuit synthesis of RS encoder and decoder can be achieved.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.07a
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• pp.53-56
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• 2010

본 논문은 Shannon의 정리에 따른 채널 용량에 근접한 성능을 보이는 것으로 알려진 터보 복호기 기반의 반복적인 검출과 복호화(Iterative Detection and Decoding) 기법에서 반복적인 복호화를 수행할 시에 제외되었던 리스트 구 복호기(List Sphere Decoder)에서 사전 정보(prior information)을 이용할 수 있도록 하여 수정된 IDD 기법을 제안하였다. 기존의 기법에서는 사후확률(A posteriori probability)을 계산하기 위하여 리스트 구 복호기를 사용하였으나 반복적인 복호화 수행 시에는 사전 정보를 이용하지 않는 특성으로 인하여 제외된다. 만약 잡음(noise) 등의 이유로 검출된 심볼 벡터 목록이 원래의 것과 매우 다른 경우라도 재 검출을 하지 않기 때문에 반복적인 복호화를 수행하더라도 원래의 정보에 근접하기 어렵게 된다. 본 논문에서는 이러한 기존의 기법에서 리스트 구 복호기를 터보 복호기의 Log Likelihood Ratio (LLR) 값을 사전 정보로 이용할 수 있도록 수정된 리스트 구 복호기를 제안하였다. 수정된 리스트 복호기는 반복적인 복호화를 수행 시 이전의 복호화에서 얻은 정보를 이용하여 새로이 검출된 심볼 벡터 목록을 제공하게 된다. 실제의 통신환경과 유사한 모델의 실험을 통해 수정된 IDD 기법이 기존의 IDD로 구성되는 내부 피드백에 RS 복호기 기반의 외부 피드백으로 구성된 형태로 피드백 회수가 증가할수록 기존의 IDD에 비해 성능이 개선됨을 확인하였다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.9B
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• pp.1616-1623
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• 1999

This paper describes error resilient coding scheme is added in WLL system and its application for robust low-bit rate still image transmission over power controlled W-CDA system Rayleigh fading channels. The baseline JPEG compressing methods are uses in image coding over wireless channel. The channel uses Reed-Solomon(RS) outer codes concatenated with convolutional inner codes, and truncated type I hybrid ARQ protocol based on the selective repeat strategy and the RS error detection capability. Simulation results are proved for the statistics of the frame-error bursts of the proposed system in comparison with conventional WLL system. it gains the 2 dB of the Eb/No in same BER.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.285-288
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• 2000

In this paper, we propose a Reed-Solomon decoder for the DVD Reed-Solomon(RS) product code based on new efficient euclid cell architecture suitable for Modified Euclid Algorithm. We synthesized the RS decoder using Hyundai 0.65um CMOS standard cell library and compared the performance of the decoder with one of the conventional architectures. The result shows that the proposed euclid cell use about 32% less symbol time.

• Journal of Broadcast Engineering
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• v.15 no.5
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• pp.681-696
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• 2010

In this paper, we examined the possibility of the transmission capacity increase by an extension and a modification of ATSC 8-VSB transmission system[1] for broadcasting a 3D HDTV services through 6 MHz terrestrial channel. First we examined the performance and the limit of conventional ATSC 8-VSB transmission system. After that LDPC & BCH code are employed instead of conventional RS & TCM code and the transmission parameter is founded for the capacity increase with resonable TOV by varying the code-rates and increasing the modulation constellation. We do not consider the perfect backward compatibility for maximum transmission capacity increase like DVB-S2 system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.907-910
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• 2009

This paper is the FPGA Implementation of Reed-Solomon Encoder that is one of Error control Codes. Reed-Solomon codes are block-based error control codes with a wide range of applications in digital communications. RS codes are strong on burst errors because it process signals as symbol. We simulate this system using Matlab from Mathworks and design it using System Generator from Xilinx. We refer Matlab source in Implementation of Reed-Solomon Error Control Coding for Compressed Images by Simon Anthony Raspa.

• Food Science and Preservation
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• v.19 no.2
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• pp.216-222
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• 2012

The optimum annealing conditions of corn starch slurry were studied for RS4 type resistant starch production by phosphorylated cross-linking. When a corn starch slurry was cross-linked by using phosphate salts (STMP/STPP mixture) in the presence of 0.9%, 1.2% and 1.5% NaOH/st.ds, a high concentration of NaOH resulted in a rapid increase of the RS contents at the early reaction stage. However, similar RS contents were obtained after 12 h of cross-linking regardless of NaOH concentrations. The annealing treatment was conducted under various conditions such as pH between 2-10, temperature $40-60^{\circ}C$, time 0-14 h followed by phosphorylated cross-linking. The lower slurry pH was for the annealing treatment, the higher RS contents were obtained after cross-linking. When the slurry annealed for various period of time and temperature, a maximal amount of RS was formed after 2 h of annealing at $50^{\circ}C$ of annealing temperature of the starch slurry (pH 2.0). Therefore, an optimal annealing conditions at pH 2.0 and $50^{\circ}C$ for 2 h were proposed under the cross-linking conditions of sodium sulfate 10%/st.ds, NaOH 1.2%/st.ds and 12 h of the reaction time. The RS contents were linearly increased with the increase of phosphate salt addition. The RS4 prepared under the optimal conditions contained RS 72.3% and its phosphorus content was 0.36%/st.ds, which was below the limit (0.4%/st.ds) of modified starch by Korea Food Additives Code.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.9C
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• pp.848-854
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• 2009

DVB-SSP is a new broadcasting system for hybrid satellite communications, which supports mobile handhold systems and fixed terrestrial systems. An upper layer, including erasure Reed-Solomon error correction combined with cyclic redundancy check. However, a critical factor must be considered in upper layer decoding. If there is only one bit error in an IP packet, the entire IP packet is considered as unreliable bytes, even if it contains correct bytes. If, for example, there is one real byte error, in an If packet of 512 bytes, 511 correct bytes are erased from the frame. Therefore, this paper proposed upper layer decoding methods; hybrid decoding. By means of simulation we show that the performance of the proposed decoding algorithm is superior to that of the conventional one in AWGN channel and TI channel.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7C
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• pp.659-664
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• 2006

We propose two error correcting algorithms for high-density optical storage systems. The first algorithm reduces the false-erasure declaration by reducing the sensitivity on random errors and increases the code rate using a simple erasure indication method. The second one exploits just the known indicator flag instead of error correcting code such as Reed-Solomon(RS) code. The proposed algorithms are superior to the error correcting algorithms of conventional systems such as DVD and BD.