• 제목/요약/키워드: interleaving

검색결과 257건 처리시간 0.028초

Enhancing the Image Transmission over Wireless Networks through a Novel Interleaver

  • El-Bendary, Mohsen A.M.;Abou-El-Azm, A.E.;El-Fishawy, N.A.;Shawki, F.;El-Tokhy, M.;Abd El-Samie, F.E.;Kazemian, H.B.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권9호
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    • pp.1528-1543
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    • 2011
  • With increasing the using of wireless technologies in essential fields such as the medical application, this paper proposes different scenarios for the transmission of images over wireless networks. The paper uses the IEEE ZigBee 802.15.4 for applying the proposed schemes. It is a Wireless Personal Area Network (WPAN). This paper presents a novel chaotic interleaving scheme against error bursts. Also, the paper studies the proposed interleaver with the convolutional code with different constraint lengths (K). A comparison study between the standard scheme and proposed schemes for image transmission over a correlated fading channel is presented. The simulation results show the superiority of the proposed chaotic interleaving scheme over the traditional schemes. Also, the chaotic interleaver packet-by-packet basis gives a high quality image with (K=3) and reduces the need for the complex encoder with K=7.

인터리빙 동작을 위한 하단 인덕터를 갖는 3-Level Boost Converter (3-Level Boost Converter Having Lower Inductor for Interleaving Operation)

  • 이강문;백승우;김학원;조관열;강정원
    • 전력전자학회논문지
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    • 제26권2호
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    • pp.96-105
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    • 2021
  • Large-scale power converters consist of series or parallel module combinations. In these modular converter systems, the interleaving technique can be applied to improve capacitor reliability by reducing the ripple of the I/O current in which each module operates as a phase difference. However, when applying the interleaving technique for conventional three-level boost converters, the short-circuit period of the converter can be an obstacle. Such problem is caused by the absence of a low-level inductor of the conventional three-level boost converter. To solve this problem, a three-level boost converter with a low-level inductor is proposed and analyzed to enable interleaved operation. In the proposed circuit, the current ripple of the output capacitor depends on the neutral point connections between the modules. In this study, the ripple current is analyzed by the neutral point connections of the three-level boost converter that has a low-level inductor, and the effectiveness of the proposed circuit is proven by simulation and experiment.

무선암호시스템에서 전송성능 개선을 위한 동적할당 알고리듬 (Dynamic Allocation Algorithm for enhancement of transmission performance on a radio encryption system)

  • 홍진근;윤장홍;장병화;황찬식
    • 정보보호학회논문지
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    • 제11권1호
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    • pp.3-12
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    • 2001
  • 본 논문은 무선채널에서 안전한 암호통신을 위해 동기식 스트림 암호시스템을 설계하였다 페이딩 채널에서 설계된 스트립 암호를 통해 암호문을 전송할 때 한 주기 동안 발생하는 동기패턴, 세션키, 암호문 정보에 적합한 인터리빙 기 법을 설계하여 전송함으로써 버스트 오류로부터 암호문을 보호하고 전송성능을 개선하여 robust한 암호통신을 가능하도록 하였다. 본 논문에서는 동적인 인터리빙 depth를 갖는 DAA를 적용함으로써 정적인 인터리빙 depth를 갖는 SAA (static allocation algorithm)보다 전송성능 개선을 얻었다.

On-the-fly 인터리빙 방식의 터보코덱의 아키텍쳐 설계 (Architecture Design of Turbo Codec using on-the-fly interleaving)

  • 이성규;송낙운;계영철
    • 정보처리학회논문지C
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    • 제10C권2호
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    • pp.233-240
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    • 2003
  • 본 논문에서는 IMT-2000용 터보코덱의 개선된 아키텍쳐를 제안하였다. 이는 on-the-fly 인터리빙 쉬프트 레지스터를 이용하여 외부 RAM을 사용하지 않는 인터리버에 의한 부호기와 필요한 메모리의 양을 줄이기 위한 복호기로 구성되었다. 제안된 구조는 C/VHDL 언어를 이용하여 시뮬레이션을 수행하여 반복횟수, 인터리버 블록크기, 부호율에 따른 비트오류율 성능이 이전 데이터와 비교적 일치함을 확인하였다.

Polarization-Independent Multiwavelength-Switchable Filter Based on Polarization Beam Splitter and Fiber Coupler

  • Lee, Yong-Wook
    • Journal of Electrical Engineering and Technology
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    • 제4권3호
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    • pp.405-409
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    • 2009
  • A polarization-independent multiwavelength-switchable fiber filter is proposed based on a polarization beam splitter and fiber coupler, which can function as a polarization-independent transmission or reflection-type interleaving filter. The proposed filter consists of a polarization beam splitter and a Sagnac birefringence loop composed of a 50:50 coupler, high birefringent fibers, and two quarter-wave plates. In the proposed filter, a transmission-type interleaver with a channel isolation > 18 dB or a reflection-type one with a channel isolation of ${\sim}3$ dB, whose channel spacing and switching displacement were 0.8 and 0.4 nm in common, respectively, could be obtained. A channel interleaving operation could be performed by the proper control of waveplates within the Sagnac birefringence loop.

Efficient Exponentiation in Extensions of Finite Fields without Fast Frobenius Mappings

  • Nogami, Yasuyuki;Kato, Hidehiro;Nekado, Kenta;Morikawa, Yoshitaka
    • ETRI Journal
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    • 제30권6호
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    • pp.818-825
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    • 2008
  • This paper proposes an exponentiation method with Frobenius mappings. The main target is an exponentiation in an extension field. This idea can be applied for scalar multiplication of a rational point of an elliptic curve defined over an extension field. The proposed method is closely related to so-called interleaving exponentiation. Unlike interleaving exponentiation methods, it can carry out several exponentiations of the same base at once. This happens in some pairing-based applications. The efficiency of using Frobenius mappings for exponentiation in an extension field was well demonstrated by Avanzi and Mihailescu. Their exponentiation method efficiently decreases the number of multiplications by inversely using many Frobenius mappings. Compared to their method, although the number of multiplications needed for the proposed method increases about 20%, the number of Frobenius mappings becomes small. The proposed method is efficient for cases in which Frobenius mapping cannot be carried out quickly.

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An Autonomic -Interleaving Registry Overlay Network for Efficient Ubiquities Web Services Discovery Service

  • Ragab, Khaled
    • Journal of Information Processing Systems
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    • 제4권2호
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    • pp.53-60
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    • 2008
  • The Web Services infrastructure is a distributed computing environment for service-sharing. Mechanisms for Web services Discovery proposed so far have assumed a centralized and peer-to-peer (P2P) registry. A discovery service with centralized architecture, such as UDDI, restricts the scalability of this environment, induces performance bottleneck and may result in single points of failure. A discovery service with P2P architecture enables a scalable and an efficient ubiquities web service discovery service that needs to be run in self-organized fashions. In this paper, we propose an autonomic -interleaving Registry Overlay Network (RgON) that enables web-services' providers/consumers to publish/discover services' advertisements, WSDL documents. The RgON, doubtless empowers consumers to discover web services associated with these advertisements within constant D logical hops over constant K physical hops with reasonable storage and bandwidth utilization as shown through simulation.

컨버터의 출력전압 리플 저감을 위한 새로운 병렬운전 방법에 대한 연구 (A Novel Paralleling Method of Converters for Reduction of Hippie in Output Voltage)

  • 박성우;박희성;장진백;장성수;김종덕
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2004년도 학술대회 논문집
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    • pp.237-240
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    • 2004
  • For the paralleled operation of DC/DC converters, the current sharing between each modules is the most important for the reliability of the power system. Interleaving method is commonly used with many paralleling schemes for the reduction of the ripple in the output voltage of paralleled converters and there are many commercial IC for interleaving application appliable. But for all of them, it is impossible to detect the number of module in operating and then change the phase of them automatically. In this paper, a novel paralleling method is proposed for the converter parallel operation, which detects the number of modules in active and sets the phases of PWM signals applied to each modules autonomously. This can greatly improve the output voltage ripple and reliability of the system. The expandibility of modular number can be done very easily by just adding several parts.

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위상이동차를 이용한 수축 생성기의 분석 (Analysis of Shrinking Generator Using Phase Shifts)

  • 황윤희;조성진;최언숙
    • 한국정보통신학회논문지
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    • 제14권11호
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    • pp.2507-2513
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    • 2010
  • 원시다항식을 특성다항식으로 갖는 두 개의 LFSR로 구성된 수축 생성기를 삽입 생성기로 해석하고, 생성된 수열들 간의 위상이동차(phase shift)에 대하여 분석한다. 또한 위상이동차를 이용하여 수축 생성기에 의하여 생성된 수열의 부분수열을 알 때 나머지 수열을 구하는 방법을 제안한다.

펄스다중화 보조회로를 이용한 새로운 구조의 36-펄스 전압원 컨버터 (New Configuration of 36-pulse Voltage Source Converter Using Pulse-Interleaving Auxiliary Circuit)

  • 전영수;백승택;한병문
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제54권5호
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    • pp.238-244
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    • 2005
  • This paper proposes a new configuration of 36-pulse voltage source converter which consists of two 6-pulse bridges and a pulse-interleaving auxiliary circuit. The system topology of proposed converter was derived to increase the pulse number of converter output voltage without increasing the number of 6-pulse bridges. The gate pulse generation was analyzed using the theoretical approach of multi-pulse switching converter, The operational feasibility of proposed system was verified by computer simulations with PSCAD/EMTDC software and experimental works with 2kVA hardware prototype. The proposed converter can be widely used for the uninterruptible power supply, the power quality compensator, and the distributed power generation, such as solar and fuel cell power system.