• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.6
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• pp.17-21
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• 2017

Since holographic data storage has the advantage of high recording density and data transfer rate, it is a candidate for the next generation storage systems. However, Holographic data storage system is affected by interpage interference and two dimensional intersymbol interference. Also, burst error occurs by physical impact. In this paper, we propose an LDPC product code using modified log-likelihood ratio and extrinsic information to correct burst error and improve performance of holographic data storage. The performance of proposed LDPC product code is 0.5dB better than that of the conventional LDPC code.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.5
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• pp.203-216
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• 2004

Recent advances in video coding technology have resulted in rapid growth of application in mobile communication, With this explosive growth reliable transmission and error resilient technique become increasingly necessary to offer high quality multimedia service. In this paper, we present the result of our investigation on the error resilient performance evaluation of the MPEG-4 simple profile under the H.324/M and the H.264/AVC baseline under the IP packet networks. Especially, we have tested error resilient tools of MPEG-4 simple profile such as resynchronization marker insertion, data partitioning, and of H.264/AVC baseline such as the flexible macroblock ordering (FMO) scheme. The objective quality of decoded video is measured in terms of rate and PSNR under various random bit and burst error conditions.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.2 no.3
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• pp.9-16
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• 2003

In this paper, we propose the burst error reduction (BER) algorithm for VoIP service in the wireless LAN network. In end point device, this BER algorithm can be achieved packet loss bounded QoS provisioning using interleaving in buffering and FEC (Forward Error Correction) through transmitting voice packet. BER algorithm can reduced the voice packet loss rate 5.5%-60% in VoIP network using wireless LAN.

• 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.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.248-251
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• 2007

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.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.5
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• pp.3-7
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• 2017

Holographic data storage system (HDSS) features short access times, high storage capacities, and fast transfer rates, since the data is recorded and read not by lines but by pages within a volume of holographic material. Burst error caused by physical impact on the high density storage system becomes very longer than that of conventional storage systems. This paper proposes an LDPC product code using two LDPC code to resolve burst error. When a total code rate is similar, the performance of two LDPC code having high code rate is better than that of one LDPC code having low code rate. Also, with error factors of two-dimensional intersysbol interference and misalignment, the proposed scheme can improve the performance in holographic data storage system.

• Journal of the Optical Society of Korea
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• v.6 no.4
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• pp.172-179
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• 2002

Like the conventional digital storage systems, volume holographic memory can be deteriorated by burst errors due to its high-density storage characteristics. These burst errors are used byoptical defects such as scratches, dust particles, etc. and are two-dimensional in a data page. To deal with these errors, we introduce some concepts for describing them and propose efficient two- dimensional interleaving schemes. The schemes are two-dimensional lattices of an error-correction code word and have equilateral triangular and square structures. Using these structures, we can minimize the number of code words that are interleaved and improve the efficiency of the system. For large size burst errors, the efficient interleaving structure is an equilateral triangular lattice. However, for some small size burst errors, it is reduced to a square lattice.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8A
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• pp.644-649
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• 2003

Novel 622Mb/s burst-mode clock and data recovery (CDR) circuits with muxed oscillators are realized for passive optical network (PON) application. The CDR circuits are implemented with 0.35$\mu\textrm{m}$ CMOS process technology. Lock is accomplished on the first data transition and data are sampled in the optimal point. The experimental results show that the proposed CDR circuits recover the incoming 400Mbps-680Mbps burst mode input data without error.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.6
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• pp.736-745
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• 2002

In network delivery of compressed video, packets may be lost if the channel is unreliable like Internet. Such losses tend to of cur in burst like continuous bit-stream error. In this paper, we propose an effective error-concealment approach to which an error resilient video encoding approach is applied against burst errors and which reduces a complexity of error concealment at the decoder using data hiding. To improve the performance of error concealment, a temporal and spatial error resilient video encoding approach at encoder is developed to be robust against burst errors. For spatial area of error concealment, block shuffling scheme is introduced to isolate erroneous blocks caused by packet losses. For temporal area of error concealment, we embed parity bits in content data for motion vectors between intra frames or continuous inter frames and recovery loss packet with it at decoder after transmission While error concealment is performed on error blocks of video data at decoder, it is computationally costly to interpolate error video block using neighboring information. So, in this paper, a set of feature are extracted at the encoder and embedded imperceptibly into the original media. If some part of the media data is damaged during transmission, the embedded features can be extracted and used for recovery of lost data with bi-direction interpolation. The use of data hiding leads to reduced complexity at the decoder. Experimental results suggest that our approach can achieve a reasonable quality for packet loss up to 30% over a wide range of video materials.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.10
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• pp.9-15
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• 2009

In this paper, we invented a new structure of fast ATC(Automatic Threshold Control) circuit. Using the structure we made a new burst-mode limiting amplifier with fast ATC function using commercial $0.8{\mu}m$ BiCMOS technology. It's ATC function worked so fast that even the first bit of burst-data could be detected, which confirmed that the new structure was useful for fast ATC. However, in the beginning of a burst, distortions in duty-cycle occurred and increased up to 59% of duty-cycle as amplitude of input signal increased. But we confirmed that after 10 cycles passed, duty-cycles was staying below 52% of duty-cycle for any magnitude of input signal.