• Title/Summary/Keyword: wireless broadcasting

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UWB based MODEM Technology and RFIC Property Overview for Wireless Human Body Communication (인체 무선통신용 소출력 UWB변복조 기술개발 및 RFIC화에 관한 연구)

  • Cha, Jae-Sang;Kim, Eun-Cheol;Kim, Jin-Young;Kim, Jai-Hyun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.5
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    • pp.133-138
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    • 2009
  • In this paper, we propose a ZCD (Zero Correlation Duration) code based Ultra Wide Band(UWB) MODEM(modulation and demodulation) technique for WBAN as a hunman body wireless communication operating in WBAN (Wireless Body Area Network) environment. We certified ZCD code based UWB schemes are available for hunman body wireless communications by various simulation and performance analysis using WBAN transmission channels. Furthermore, we suggested some possibility of RFIC implementation related to human body based UWB communication module by presenting some related examples.

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Wireless Access Technologies for Smart Highway: Requirements and Preliminary Results (스마트하이웨이 무선전송기술: 요구사항 및 기본시험결과)

  • Cho, Woong;Oh, Hyun-Seo;Park, Byoung-Joo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.2
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    • pp.237-244
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    • 2011
  • Vehicular communications extend their application areas by combining communication technologies with roads/vehicles, and one of major applications is Smart Highway project. Smart Highway is a new advanced highway system which enhances the current highway system in Korea by improving reliability, safety and convenience. In this paper, we introduce wireless access technologies for vehicular communications especially focusing on Smart Highway. We first introduce the overall communication system architecture and the basic service and communication requirements for Smart Highway. Then, we discuss wireless access technologies including L2-level hand-over scheme. In addition, the results of experimental measurements of Wireless Access in Vehicular Environments (WAVE) system are introduced.

A Study on Wireless Network Management for Security Enhancement (보안강화를 위한 무선 네트워크 관리 방안에 관한 연구)

  • Lee, Eun-Sub;Kim, Young-Kon
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.3
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    • pp.195-200
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    • 2020
  • Wireless LANs are being used in many fields due to their ease of use. The biggest advantage of the WLAN can be said above all mobility. Domestic wired internet service has been saturated since 2006, but wireless internet users have been steadily increasing. However, WLAN has many advantages and characteristics of wireless service. It has a number of security vulnerabilities, and various security related technologies have been developed and applied to solve these problems. On the other hand, security awareness of WLAN users is still insufficient, and security accidents such as personal information leakage occur repeatedly every year. We will study the main weaknesses that can occur in WLAN and suggest security measures from the management level.

Study on Verification Evaluation of Wireless Network Introduction for Waterworks Supervisory and Control (수도사업장 감시제어를 위한 무선통신망 도입 신뢰성검증 연구)

  • Lee, An-Kyu;Park, Eun-Chul;Lee, Dong-Hoon;Hong, Sung-Taek;Kim, Nam
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.9 no.6
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    • pp.195-200
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    • 2009
  • In this paper, we verified the reliability through local examination by introducing a wired network that is operated at the local waterworks to wireless LAN based Wi-Fi network. The adopted wireless network compared to the existing wired network through saving cost and reducing breakdown points have been proven to be effective qualitatively and quantitatively. This study proved that wireless networks could be introduced for the advancement of operations management of existing metropolitan water supply and the local waterworks that are operating currently.

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Design of Visual Surveillance System based on Wireless High Definition Image Transmission Technology (무선 고해상도 영상 전송 기술에 기반한 영상 감시 시스템의 설계)

  • Kim, Won
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.5
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    • pp.25-30
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    • 2012
  • It is important to detect dangerous objects which are intentionally abandoned in public places. Nowadays visual surveillance system is required to enhance the performance in two ways : high resolution and wireless linking ability. In this study the design of visual surveillance system is newly proposed to detect abandoned objects for social security purpose based on wireless high resolution image transmission technology. Also, to enhance PED, PAT performance, the tracking algorithm is included in the previous visual surveillance software scheme. By implementing proposed design scheme on the real wireless high resolution image transmission system, the effectiveness of the overall system is shown with the transmission performance of 4.0 Gbps speed.

Design and Implementation of Real-Time Vehicle Safety System based on Wireless Sensor Networks (무선 센서 네트워크 기반의 실시간 차량 안전 시스템 설계 및 구현)

  • Hong, YouSik;Oh, Sei-JIn;Kim, Cheonshik
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.8 no.2
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    • pp.57-65
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    • 2008
  • Wireless sensor networks achieve environment monitoring and controlling through use of small devices of low cost and low power. Such network is comprised of several sensor nodes, each having a microprocessor, sensor, actuator and wired/wireless transceiver inside a small device. In this paper, we employ the sensor networks in order to design and implement a real-time vehicle safety system. Such system can inform the safe velocity in a specific weather condition to drivers in advance through analyzing the weather data collected from sensor networks. As a result, the drivers can prevent effectively accidents by controlling their car speed.

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Effectiveness of DUPACK-independent TCP in Coded Wireless Mesh Networks (중복 승인을 사용하지 않는 TCP의 코드화된 무선 메쉬 망에서의 효과)

  • Lim, Chan-Sook
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.1
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    • pp.7-13
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    • 2011
  • While the TCP throughput degradation problem in coded wireless mesh networks is well-known, few effective solutions have been proposed. Most schemes proposed attempts to mask packet reordering by ordering packets at a lower layer or to adjust a packet transmission rate to solve the scarcity problem of coding opportunities. Through the throughput comparison of traditional standard TCP variants, we show that losses and duplication of TCP acknowledgements in coded wireless mesh networks can impact throughput. In addition, we show that a TCP variant that does not rely on duplicate acknowledgements is more suitable for coded wireless mesh networks.

Study of direction acquisition using signal sensitivity wireless LAN (무선랜 신호감도의 인식센서화를 이용한 방향 인식 연구)

  • Sim, Gyuchang;Lim, Seung-Cheol
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.5
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    • pp.161-167
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    • 2012
  • Portable devices such as smartphones with built-in wireless LAN to the prevalence of anyone using. But the wireless Internet connection and positioning services are limited to high-quality wireless service, they may not be available. Thus, wireless LAN infrared sensor in the same way as with angry alternative way wireless capabilities of the application automatically identify the location of the Sensor application as an alternative method is proposed. Thus, wireless LAN, such as infrared sensors and other alternzative methods of wireless features in a way where the application can recognize and automatically recognize the sensor application as an alternative method is proposed. Sensor is signals between wireless LAN and access points using the sensitivity, WLAN antenna with omni-directional signal output operation of the sensor is assumed to be recognize this by putting a direction to obtain through the proposed algorithm, Sensors such as photo-coupler without direct recognition sensor, wireless LAN and access points, the same function as the connection between the sensitivity to perform its function was to utilizing.

Channel Estimation and Prediction in Cross-Layer Design Using Side-information (크로스레이어 디자인에서 사이드 인포메이션을 활용한 채널 추정 및 예측)

  • Cho, Yong-Ju;Cha, Ji-Hun;Kim, Wook-Joong
    • Journal of Broadcast Engineering
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    • v.16 no.5
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    • pp.797-800
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    • 2011
  • The objective of MPEG Media Transport (MMT), which is on going standard, is to develop efficient delivery of media over packet based networks in an adaptive, progressive, download/streaming fashion over various IP based networks, including terrestrial, satellite and cable broadcast networks. In this paper we introduce utilization of signal strength information based on Cross Layer Design(CLD) to efficient multimedia delivery over wireless network in which in practice the wireless conditions can vary significantly. Many recent studies have shown that a significant improvement in wireless video throughput can be achieved by utilizing signal strength information on CLD [1][2]. Despite of its usefulness, however, it was difficult to employ signal strength information in rate adaptation applications due to different representation of signal strength information for each underlying wireless network. To that end, we proposed syntax and semantics of signal strength information in such a way that the information can be interpreted in the unified way. The proposed signal strength information was proposed for the MMT standardization.

A Greedy Algorithm for Minimum Power Broadcast in Wireless Networks (무선 네트워크에서 최소전력 브로드캐스트를 위한 탐욕 알고리즘)

  • Lee, Dong-ho;Jang, Kil-woong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.05a
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    • pp.641-644
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    • 2016
  • Unlike wired networks, broadcasting in wireless networks can transmit data at once to several nodes with a single transmission. For omnidirectional broadcast to a node in wireless networks, all adjacent nodes receive the data at the same time. In this paper, we propose a greedy algorithm to solve the minimum power broadcasting problem of minimizing the total transmit power on broadcasting in wireless networks. We apply two matrices to the proposed algorithm: one is a distance matrix that represents the distance between each node, the other is an adjacency matrix having the number of adjacency nodes. Among the nodes that receive the data, a node that has the greatest number of the adjacent node transmits data to neighbor preferential. We compare the performance of the proposed algorithm with random method through computer simulation in terms of transmitting power of nodes. Experiment results show that the proposed algorithm outperforms better than the random method.

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